ST. XAVIER‟S SCHOOLS-CHANDIGARH, PANCHKULA, MOHALI, ZIRAKPUR

Class 9 English Worksheet-4 (Language)

VERBS AND TENSES

A Verb is an action word that tells us what someone or something is doing.

It may refer to the (1) present time (2) past time (3) future time .

A Verb that refers to present time is said to be in the Present Tense

A Verb that refers to past time is said to be in the Past Tense.

A Verb that refers to future timeis said to be in the Future Tense

Thus there are three main Tenses:The Present, The Past,The Future.

The Tense of a Verb shows the time of an action.

The forms of the PRESENT TENSE are:

1. Simple Present e.g. write/ writes

2. Present Continuous e.g. am/is/are writing

3. Present Perfect e.g. has/have written

4. Present Perfect Continuous e.g. has/have been writing

The forms of the PAST TENSE are:

1. Simple Past e.g. wrote

2. Past Continuous e.g. was / were writing

3. Past Perfect e.g.had written

4. Past Perfect Continuous e.g. had been writing

The forms of the FUTURE TENSE are:

1. Simple Future e.g. will write

2. Future Continuous e.g. will be writing

3. Future Perfect e.g. will have written

4. Future Perfect Continuous e.g. will have been writing

EXERCISE 1

Fill in the blanks with the correct form of the word given:

1. I .....two chapters of this book.(write)

2. He .....butter on a piece of bread.( like)

3. They .....eating an hour ago.(finish)

4. We .....tea in the afternoon.(take)

5. He .....the movie on Sunday.(watch)

6. The doctor .....the life of the child.(save)

7. She .....me a nice gift.(give)

8. I practice .....verbs for one week.(practice)

9. We .....our seats before the show began.(take)

10. He .....his favourite novel in the library.(read)

EXERCISE 2

Fill in the blanks with the correct form of the word given

1. The earth ..... around the sun.(revolve)

2. Tomorrow I ..... for Dubai.(leave)

3. I .....to the beach next Sunday.(go)

4. They .....football next Sunday.(play)

5.Julia .....her assignment before the boss arrived.(complete)

6. I ..... to go for a walk.(use)

7. She .....to learn French for one month.(try)

8. The teacher .....the lecture.(deliver)

9. When I opened my eyes, I .....a strange sight.(see)

10. The students.....their dialogues.(rehearse)

EXERCISE 3

Fill in each blank with a suitable form of the word given in brackets:

Napoleon was....(involve) in a conversation with a colonel of a Hungarian battalion

who.....(take) prisoner in Italy. The colonel mentioned that he.....(fight)in the army

of Maria Theresa. ―You must have a few years under your belt!‖ ....(exclaim) Napoleon. ―I‘m sure I‘ve lived sixty or seventy years,‖ .....(reply) the colonel.

―You mean to say,‖ Napoleon continued, ― you.....(not keep) track of the years you.....(live)?‖

The colonel promptly replied, ― Sir, I always count my money ,my shirts, and my horses, but as far as for my years, I know nobody who wants.....(steal) them, and I

shall surely never lose them.‖

EXERCISE 4

Fill in each blank with a suitable form of the word given in brackets:

A giant plane, ......(carry) 43 passengers was forced to crash land when its ....(land)

gear got stuck. Only the skill of the pilot.....(prevent) a major tragedy. The landing

gear .....(not come) down as it prepared to land at the airport. Expert mechanics

laboured over the plane for three hours before they found what caused the

mechanical.....(fail ). What they found was almost unbelievable.

A nut about as small as a pencil eraser ....(fall) into a channel, or had been picked

up on the runway, and had prevented a pin from being withdrawn. This in turn kept

the gear from ( move).

Small things , often determine the well being of countless people. One incident can

endanger the ....( safe) of a large number of people.

EXERCISE 5

Fill in each blank with a suitable form of the word given in brackets:

The American Academy of Pediatrics .......(recommend) 60 minutes of daily

unstructured free play as an essential part of children‘s physical and mental health and social development. Back in the day, children.....(see)........(play) various local

games that.....(keep) a child‘s metabolism.......(tick) and ......(help) the body grow. Today obesity is a big problem. Longer school hours, emphasis on academics,and

access to gadgets .......(lead) to a sedentary lifestyle. One hour of play a day

......(make) a huge difference.

Answer key of English Worksheet-2(Literature)

THE HEART OF THE TREE

STANZA-1

Ans 1) A tree is described as a ‗ friend of sun and sky because it shares their benefits like a friend and helps to provide cool breeze to lessen the heat of the sun and brings rain

to nurture the environment.

Ans 2) A tree gives shelter to birds by allowing them to build their nests.It protects

them from heat and rain.

Ans 3 ) A tree planter actually plants peace and harmony in the environment.

STANZA-2

Ans 1) Tree Planting is a symbolic act of goodness as the planter plants the trees not

only for himself but also for all the living objects on earth. He not only benefits the

Present generation but also the future generation.

Ans 2) Planting trees helps a nation to grow. It serves as a living legacy for the next

generation. It provides tender rain ,which is essential for our very existence.

Ans 3) The word' unborn eyes 'means the eyes that have not yet born. The poet refers to

the future generation, who will enjoy the benefits of the trees that are planted by the

Present generation

Ans 4) A plant can offer us cool shade in the scorching heat of summer ,with its leafy

branches. Moreover plants help in bringing rain which nurtures the environment.

STANZA-3

Ans 1) A tree planter does civic good by working not only for himself but also for the

welfare of others. He blesses his neighborhood by sharing the benefits provided by the

tree he plants.

Ans 2) The man who plants a tree holds the growth of all our land (the entire world) in

his hand. The entire earth is the land that the poet has in mind.

Ans 3) The title of the poem ‗ The heart of the tree‘ is appropriate. The poem describes

the innumerable benefits of trees. People who plant trees plan a harmonious environment

for the future generation.Trees provide us pure air to breathe as the heart provides pure

blood for the survival of human beings.

……………………………..,......................................................................,,.,

Answer key of English Worksheet-3 (Literature)

THE COLD WITHIN ( POETRY)

STANZA-1 Ans 1) The bitter cold climate brought the six humans together by chance.

Ans 2) Each one of them possessed a stick of wood in their hands.

Ans 3) Each person could have given his stick of wood (log) to keep the fire burning ( to get

warmth)and could have saved each other from dying in the bitter cold.

STANZA-2 Ans 1) The first one was a woman who was a white ( American).

He ( used for a human) had noticed that one of them in the group was a black (probably

belonging to an African country.)

Ans 2 )He held back his stick because he had noticed one black

man around the fire. He suffered from racial prejudice so he refused to contribute( his log) to

the dying fire.

Ans 3) He acted out of his racial prejudice as he did not want to warm the black and save him

from the bitter cold.

STANZA-3 Ans 1) Six human beings were trapped in the bleak and bitter cold.The first was a white

woman,the second was a man who suffered from religious intolerance, the third was a poor man,

the fourth was a rich man ,the fifth was a black man and the sixth was a man who lacked

generosity.

Ans 2) They all needed a stick of wood to light the dying fire and warm themselves for their

survival.

Ans 3) The second man noticed that one of the human beings did not belong to his religion.He

did not give his stick to add fuel to the dying fire.

Ans 4) He decided not to help a person of a different religion because he suffered from the sin of

racism and intolerance.

STANZA-4 Ans 1 ) The third man was probably a poor man as he was wearing tattered ( torn and

worn out) clothes.

Ans 2) He felt that the rich do not work hard, they just exploit the poor so they do not deserve

to live. He decided not to give his stick to warm the idle rich as he had feelings of bitterness and

jealousy against the rich.

STANZA-5

Ans 1) The other three men , referred to, earlier, in the group were a white man(used for human

though it was a white woman) ,a man who lacked religious tolerance and a poor man .

Ans 2 ) His greed for money kept the rich man lost in his thoughts. He was thinking of how to

keep safe ,what he had earned, from the poor ,who he believed, were lazy and shiftless ( without

any goal in life).

Ans 3) He decided ,not to help the poor man as he felt that the poor did not deserve to survive,

they were lazy and shiftless. The rich man actually had the sins of greed and stinginess within

him.

STANZA-6

Ans 1) The poor man had feelings of bitterness and jealousy against the rich. He thinks that the

rich are idle and he should not use his log to warm the idle rich. The rich man is equally

prejudiced against the poor. He thinks that the poor are lazy and shiftless.He suffered from greed

and stinginess.

Ans 2) The black man‘s face revealed hatred and revenge for the white man.

Ans 3) The black man is full of hatred for the white people, he could hurt the white man ,

somehow ,by holding back his stick and not contributing to add fuel to the dying fire which

could help the white man to survive the bitter cold.

STANZA-7 Ans 1) Each man failed to contribute to add fuel to the dying fire (by not giving away his stick

)which would warm them and help them to survive .They all failed to overcome the petty

barriers of class, race and religion that divided them.

Ans 2) The last person was a man who lacked generosity. He was selfish and believed in giving

only for his own profit.

Ans 3) He too failed to part with his log of wood because he lacked generosity and would give

only when he could gain something in return. In this situation he saw no profit, so he did not

contribute to the dying fire.

STANZA-8 Ans 1) ‗They‘ refers to the six men who were caught in an extreme cold weather. They were all

standing around a fire to warm themselves.

Ans 2) The six men refused to share their log to fuel the dying fire and keep each other warm

because of some or the other prejudice(the cold within their hearts) .The fire died out,all were

found frozen to death in the morning.

Ans 3 ) The cold within‘ means the lack of feeling in the heart, born out of selfishness,

prejudice, malice etc. It is because of these negative feelings, that the six men do not give up

their sticks of wood which could have kept the fire burning and kept them warm ,to survive.

Because of the cold within them , these six human beings could not overcome the barriers of

class, race and religion that divided them.

…………………………………………………………………………………………………….

Class 9 Hindi Worksheet-4

Class 9 Punjabi Worksheet-4

ਜਮਾਤ ਨਵੀਂ ਦੇ ਵਵਵਦਆਰਥੀ ਵਛਲੀਆ ਂਜਮਾਤਾ ਂਵਵੱਚ ਵੀ ਨਾਂਵ ਵਚਨ ਬਾਰੇ ਵਗਆਨ ਹਾਵਿਲ ਕਰ ਚ ੱਕੇ ਹਨ।ਹ ਣ ਨਵੀਂ ਜਮਾਤ

ਵਵੱਚ ਵੀ ਇਹਨਾਂ ਸ਼ਬਦਾ ਂਅਤੇ ਵਾਕਾਂ ਦਾ ਵਲੱਖਤ ਅਵਿਆਿ ਕਰ।

_______________________________

ਅਭਿਆਸ ਦ ੇਪ੍ਰਸ਼ਨ :--

Answe key of Class- 9 Worksheet-3

ਹੇਂਠ ਵਲੱਖ ੇਵਾਕਾ ਂਦੇ ਵਲੰਗ ਬਦਲ ਕੇ ਵਲਖ। ੧- ਨੀਲਾ ਘੜਾ ਤੇਜ ਦੜਦਾ ਹ।ੈ ੨- ਮ ੰਡਾ ਗੀਤ ਗਾਉਂਦਾ ਹ।ੈ ੩- ਕਾਲਾ ਬੱਦਲ ਚੜਹ ਆਇਆ ਹ।ੈ ੪- ਮਰਨੀ ਨੇ ਵਕਰਲਾ ਖਾ ਵਲਆ। ੫- ੱਤਰ ਨੇ ਿਹ ਰਾ ਕ ੱਵਿਆ, ਜਵਾਈ ਨੇ ਵਤਓਹਰਾ ਲ ਵਿਆ। ੬- ਅਧਿਆਪਕ ਨੇ ਚਪੜਾਸਣ ਦੇ ਸਾਹਮਣੇ ਝਗੜਾਲ ੂ

ਲੜਕੀ ਨ ੰ ਿਮਝਾਇਆ। ੭- ਮੇਰੀ ਿੈਣ ਆਣੀ ਿਹੇਲੀ ਨਾਲ ਮੇਲਾ ਵੇਖਣ ਗਈ। ੮- ਧਬੀ ਨੇ ਆਣੇ ਗ ਆਂਢੀ ਤੋਂ ਮਦਦ ਲੈਣ ਲਈ ਬੇਨਤੀ ਕੀਤੀ। ੯-ਧਬੀ ਨੇ ਆਣੀ ੰਜਾਬੀ ਦੀ ਰਵਿੱਧ ਕਵਵੱਤਰੀ ਦੀ ਕਵਵਤਾ ੜਹ ਕੇ ਿ ਣਾਈ। ੧੦- ਮੈਂ ਆਣੇ ਿਹ ਰ,ੇਦਦਹ ੇਿ ਅਤੇ ਨਨਾਣਵਇਏ ਦੀ ਬਹ ਤ ਇੱਜ਼ਤ ਕਰਦਾ ਹਾ।ਂ ੧੧- ਬੱਕਰੇ ਨੇ ਘਾਹ ਖਾ ਵਲਆ। ੧੨-ਿਿੱ ਨੇ ਆਣੇ ੱਤਰ ਲਈ ਕਾਰ ਖਰੀਦੀ। ੧੩- ਉਿ ਨੇ ੀਲੇ ਰੰਗ ਦੀ ਗੜੀ/ ਚ ੰਨੀ ਬੰਨਹ ੀ ਹਈ ਹ।ੈ ੧੪- ਬਾਗ ਵਵੱਚ ਮਰਨੀ ੈਲ ਾ ਰਹੀ ਹ।ੈ ੧੫- ਅਮਰਜੀਤ ਦਾ ਮ ੰਡਾ ਬਹ ਤ ਚਲਾਕ ਹ।ੈ

Class 9 History & Civics Worksheet-3

SALIENT FEATURES OF OUR CONSTITUTION

Meaning of Constitution : A Constitution is a framework of well defined laws

according to which a State(country) is governed .

Date of Adoption of Constitution : 26th

November, 1949

Date of Enforcement of Constitution : 26th

January , 1950

Single Citizenship : According to the Indian Constitution , every Indian citizen holds

the citizenship of the country only and not of the state to which he belongs or resides in .

For example , a resident of Punjab will hold the citizenship of India only and not that of

Punjab .

Universal Adult Franchise : Every Indian citizen (irrespective of his caste, colour,

creed, religion, gender) on attaining the age of 18 years gets the right to vote and elect

the representative of his choice .

Fundamental Rights : These are the basic rights given to every Indian citizen by

the Constitution of India , in order to provide and support the all-round

development of every individual without any discrimination . There are six

categories of Fundamental Rights included in Part-III of the Indian Constitution .

Fundamental Duties : The Indian Constitution defines Fundamental Duties as the

moral obligations of every Indian citizen to promote the spirit of patriotism , unity

and integrity of India . It is included in Part IV-A Section 51-A of the

Constitution. There are total 10 Fundamental Duties .

Directive Principles of State Policy : As per the Indian Constitution , these

principles act as guidelines for the government and form the basis of various laws

, policies and programmes framed by the government .

Welfare State : It is a concept of the Government , wherein the State (country )

plays a vital role in the economic , social and political well-being of the citizens .

EXERCISE : Read , learn and write a detailed note on the Salient Features of the

Indian Constitution .

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Answer key of S.St. Worksheet-3 (History Civics-2)

Q.1 Mention the various names of Harappan Civilisation .

Ans.1 (a) Indus Valley Civilisation (b) Bronze Age Civilisation

Q.2 Write a short note on the following :

Ans.2 (a) Dancing girl - It is a bronze statue of a dancing girl which shows her in a

relaxing posture (after a dance performance). It was found at Mohenjodaro . She can be

seen wearing various ornaments .

(b) Bearded Man - A stone sculpture of a bearded man was found at

Sindh(Pakistan) . This figure is known as that of a Priest King . The statue can be seen

wearing ornaments , draping a shawl , having a trimmed beard, half closed eyes,etc. The

appearance of the man in the statue represents him as a priest or a king or both .

Q.3 Discuss the features of :

Ans.3 (a)Great Bath - It was a water storage tank & as used for various purposes . It

was excavated from Mohenjodaro . It had huge storage capacity , proper drainage system,

attached staircase & it was made of burnt bricks.

(b) Citadel - It referred to that part of the city which included important buildings , like,

great granary , workshops , palaces, etc. . All these buildings were made on raised

platform . This area depicted centralized authority .

Q.4 Name the various sources of Harappan Civilisation .

Ans.4 The main sources of Harappan Civilisation are the archaeological evidences , like,

ruins of cities , seals, pottery, toys , ornaments, tools , weapons , etc.

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Class 9 Geography worksheet-3

Structure of the Earth ( Interior of the Earth)

The Earth has a solid outer shell like mercury Venus and Mars which are classified

as terrestrial planets. The outer shell called the sphere is the thin outermost layer

known as mineral skin which is rich in minerals.

This layer has an average density of about 17 kilometers for the globe as a whole

containing continents and ocean basins. It is the most significant zone of the solid

Earth. All visible landforms such as mountains, plateaus , plains etc. All parts of

lithosphere where people build houses , get minerals and fertile soil which

supports plant life

To understand the Geography of external landforms of the Earth, it is necessary to

study not only the upper crust but also its interior state because many of the

physical phenomena are intimately associated with it. However, human beings

have not been able to go very deep, the deepest mines are less than 6 km deep. So,

there are some indirect means to obtain information about the interior parts of the

Earth. The temperature of the Earth's interior is increased by 1 degree Celsius for a

depth of every 32 metres.

It means that the interior part of the Earth must be very hot and no substance can

remain there in a solid state.

The geologists estimated that there is a sharp increase in the temperature of the

upper layers of the earth with depth due to the presence of radioactive minerals

like uranium and thorium which are found in abundance up to a depth of hundred

kilometres. Then the rate of increase in temperature decreases with increase in

depth.

Another important source of information is the study of earthquake waves seismic

waves. Similar to light waves seismic waves are reflected when they meet a

surface as well as refracted or bend when they travel from one medium to another.

During an earthquake the huge rocks shift on a large scale and the seismic waves

originate. These waves travel in all directions from the point of origin.

As these waves move through the material of different density, they change their

speed. Thus they arrive on the surface at different times.

By calculating the time taken by the seismic waves to reach different places and

by the travel behaviour of the shock waves generated as a result of the earthquake,

the scientists can determine the interior structure of the earth.

For example, the outer and inner core bends the primary earthquake waves, while

secondary waves are stopped by the dense liquidof the outer core.

The geologist have learnt much about the thickness and the interiors of the Earth

by recording and studying the arrival of earthquake waves with the help of

different instruments.

LAYERS OF THE EARTH

The study of earthquake waves revealed that the Earth consists of three concentric layers

from the surface of the centre. They are known as:

1. Crust.

2. Mantle.

3. Core.

THE CRUST

It is the outermost layer of the Earth that is also known as the Lithosphere. The word

―LITHOS‖ means ―rocks‖or ―stones‖ in Latin. The crust is a very thin layer having an average thickness of about 60 km that forms less than 1% of the Earth. The crust is

subdivided into two parts according to its composition.

SIAL

1. The uppermost layer of the crust is called Sial consisting of Silicate and

Aluminium (Si = silicate, Al = aluminium).

2. On an average, the thickness of Sial is till 25 km from the surface.

3. The continents are composed mainly of lighter rock material formed from silicon

and aluminium, so the Sial is thick over the continents and very thin or absent on

the ocean floor especially the Pacific Ocean.

4. The average density Sial is 2.7 gm/cc (gram per cubic centimetre).

SIMA

1. The layer below the Sial is known as Sima consisting of silicates of magnesium. (SI =

silica, MA = magnesium).

2. The average thickness of this layer is about 35 km.

3. Sima is the oceanic crust lying mainly under the oceans, composed of slightly denser

or heavier rock material.

4. The average density of Sima varies from 3.0 to 3.4 gm/cc.

Sial and Sima together from the Lithosphere or Crust. The boundary between the crust and

mantle is called the ―Moho‖ or ―Mohorovic discontinuity‖ named after the Yugoslav scientist who discovered it. The Sial being lighter than Sima, is considered floating on the

denser Sima forms the basis of Wenger's Continental Drift Theory.

The Mantle

I. This layer lies between the crust and the core.

II. The material of the mantle is composed of silicates of magnesium and iron.

III. The mean density of the mantle is 4.5 gm /cc that varies from 3.0 gm/cc at

the top to about 5.5 gm/cc at its base.

IV. The average thickness of the mantle is about 2800 km.

V. Mantle is also subdivided into two distinct parts called upper mantle and

lower mantle.

VI. The upper mantle known as the Asthenosphere is in a semi- liquid state or

in a partially molten state.

VII. Upper layer has been located through the decrease in velocity of

earthquake waves so it is also referred to as the ―lower velocity zone‖. VIII. The lower mantle is also known as the Mesosphere.

IX. The lower mantle behaves like a solid due to extreme pressure exerted by

the overlying layers.

X. The temperature in the mantle is too high. It is about at 850° C in the upper

region and 2208° C in the lower region.

XI. There is a zone of discontinuity in the density between mantle and core

known as Gutenberg Discontinuity.

Mohorovic discontinuity

It is a distinct seismic discontinuity which represents the change in composition

between the silica crust and the ultramafic mantle. It is considered to represent the

base of The crust. The 'Moho' is the boundary between the crust and the upper

mantle. It is 5 kilometres thick at the mid ocean ridges and 75 kilometre thick at

the continental shelf.

The Core

1. The central layer of the Earth is known as the core.

2. This dense layer is also known as barysphere

3. The core of the earth has a radius of about 3500 kilometres.

4. The core is composed of dense materials mainly nickel and iron or

ferrum so it is is also known as the nife(ni= nickle and fe= ferrum)

5. The core is sub divided into two parts called the outer core and the inner

core.

6. the outer core behaves like a liquid and does not let the earthquake

waves pass through it.

7. the inner core behaves like a solid layer due to extreme pressure exerted

by overlying layers.

8. the core has a dense material like iron and nickel so the density of core

is between 30g/cc to 15g/cc.

9. The temperature of the core is estimated about 5000 degree Celsius.

The iron present in the cold loses its magnetic properties at such high

temperature. The scientists think that due to rapid rotation of the earth, electric

currents originate in the liquid core,which are responsible for the formation of

magnetic field around the earth.

Based upon your reading of the above text answer the following questions

:

1. What do you mean by the term crust of the earth?

2. Name the two distinct layers of the earth‘s crust.

3. Give any three characteristics of sial.

4. Why does the inner core act as a solid layer?

5. Name the major constituent minerals of the core.

6. Give any three characteristics of the core.

7. What is Mohorovic discontinuity?

Answer key of Geography Worksheet-2

Answer 1 The equator is the greatest possible circle as the earth is bulged at the equator representing the

largest circumference of the earth. All latitude except the equator are small circles because they do not

divide the earth into two equal parts.

Answer 2 a) Equator is an imaginary great circle that runs midway between the two poles known as the

zero degree parallel of latitude that divides the earth into the northern and the southern hemisphere. The

plane of the equator intersects the earth's axis of rotation at right angle.

b) The Prime Meridian or Greenwich Meridian is the reference line for measuring east-west distance on

the earth . it is an imaginary line which converges on the to pose and passes through Greenwich near

London where there is an old observatory located.

Prime Meridian is taken as zero degree meridian. The Prime Meridian along with 180 degree longitude

divides the earth into two halves or hemispheres the eastern and the Western hemisphere.

c) The lines of latitude are imaginary lines which join all the places having the same angular distance

North or South of the equator. These latitude run parallel to the equator so they are called the parallels of

latitudes.

d)Lines of longitude are imaginary lines which join all the places having the same angular distance east or

west of the Prime Meridian. There are only 360° longitudes. The lines of longitude are also called

meridians because all the places located along a particular longitude face the overhead Sun at the same

time.

Answer 3 Properties of latitudes:

1. All attitude is the angular distance of a place North or South of the equator.

2. There are 181°parallels of latitude including the equator.

3. There is a distance of about 111 km between any two latitudes.

4. Latitude gives us a rough idea about the temperature , climate, related vegetation and the animal

life of any place.

Answer4 The network of parallels of latitude and meridians of longitudes drawn on a map or a globe

enables us to determine the location of any place on the earth and is called the geographic grid.

Answer5 Some countries like Russia Canada and USA have large longitudinal extension where if a single

time is taken as a standard time it will create a lot of problems. So to avoid such confusions the countries

having large east west extension have to follow more than one time so they have many time zones. For

example Canada and USA have 5 time zones.

Answer 6 Earth and its heat zones

Answer The important parallels of latitude

1. The Equator 0°.

2. The Tropic of Cancer 23 ½. ° North.

3. The tropic of Capricorn 23 ½ ° South

4. The Antarctic circle 66 ½ ° South.

5. The Arctic Circle 66 ½ ° North.

Class 9 Physics Worksheet-4

*Understand,learn and solve.

1.

Speed Velocity

The distance travelled per

second by a moving object

The distance travelled

per second by amoving

object in a particular

direction

It is scalar quantity .The

speed doesnot tell us to he

direction of motion

It is vector quantity .The

velocity tells us the speed

as well as the direction of

motion .

It is only positive It can be positive ,

negative and zero

2.Acceleration: Acceleration is a measure of how quickly the velocity of an object changes. So, the

acceleration is the change in the velocity, divided by the time. Acceleration has a

magnitude (a value) and a direction. It is a vector quantity.

● The SI unit of acceleration is the metre per second squared (m s−2).

3.Retardation (deceleration):

means negative acceleration. If the velocity of a body decreases,the acceleration is

negative.

a = acceleration (m/s2)

vf = the final velocity (m/s)

vi = the initial velocity (m/s)

t = the time in which the change occurs (s)

Δv = short form for "the change in" velocity (m/s)

3. Difference between acceleration and retardation.

Acceleration Retardation

It is change in velocity per unit time.It is

always positive

It is change in velocity per unit time .It is

always negative .

In this case velocity keeps increasing. In this case velocity keeps decreasing.

*Numerical problems based on the above formula.

1. A toy car accelerates from 3m/s to 5m/s in 5 s. What is its acceleration?

2. A pebble thrown vertically upwards withan initial velocity 50 m/s comes to s stop

in 5s .Find retardation.

3. A car starting from rest acquires a velocity 180 m/s in 0.05 h .Find the

acceleration.(hint - in anycase body starts from rest initial velocity =0 ).

4. A bicycle initially moving with a velocity 5 m/s accelerates for 5 s at a rate of 2

m/s^2.What will be its final velocity ?

5. A car moving on a straight path covers a distance of 1 km due east in 100 s .What

is I) the speed and ii)the velocity of car ?

6. A train takes 3 h to travel from Agra to Delhi with a constant speed of 65 km /h

.Find the distance between the two cities .

7. State the difference between speed and velocity .(4 points )

8. State the difference between acceleration and retardation .

-------------------------------------------------------------------------------------------

Answer key of Physics worksheet-3

a.. Directly proportional to the square root of its effective length. T∝√l b.Inversely proportional to the square root of acceleration due to gravity (g).

T∝ 1/g and T= 2π √l/√g

b.

Oscillation The complete to and fro motion of the pendulum constitutes

one complete oscillation.

Amplitude The maximum displacement of the pendulum, i.e., the

displacement between the mean position and the extreme

position, is called its amplitude.

Frequency The number of oscillations made by the pendulum in one

second is called its frequency of oscillation. The unit for

frequency in the SI system is the hertz (Hz).

Time Period The time taken by an oscillating pendulum to make one

complete oscillation is called its time period.

c. A pendulum with a time period of oscillation equal two seconds is known as second's

pendulum.

d. 1:1; reason - time period doesnot depend on the mass of the Bob

e. T1 :T2 = 1:4

Class 9 Chemistry Worksheet-4

LANGUAGE OF CHEMISTRY CONTINUED FROM WORKSHEET -3

COMPOUND: A pure substance is composed of two or more elements chemically

combined in a fixed ratio.

How is a compound different from an element?

ELEMENT is the simplest chemical substance in which all the atoms are exactly the

same.

Why is water a compound and not an element?

Reasons:

I. Water is composed of two elements – hydrogen and oxygen.

II. The two elements -hydrogen and oxygen in water are combined in a fixed

proportion by weight.

III. Properties of water are different from the properties of hydrogen and oxygen.

ANSWER THE FOLLOWING:

1. Name the elements present in the following compounds

a) Ammonia b) Carbon dioxide c) Sodium chloride

2. Pick out the compounds from the list below

Oxygen, Potassium nitrate, Silver chloride, Nitrogen, Helium, Chlorine,

Carbon monoxide

3. Differentiate between an element and a compound.

4. Why water is a compound and not an element?

Answer Key of Chemistry Worksheet-3

2. FORMULA VALENCY

a) SO4 -2

b) NO3 -1

c) NO2 -1

d) SO3 -2

e) S -2

f) HCO3 -1

g) HSO4 -1

3. I. NaCl II. NH4NO3 III. Fe2(SO4)3 IV. CuCl V. KNO3 VI. CaCO3

Class 9 Biology Worksheet-4

CHAPTER-POLLINATION AND FERTILIZATION (PART-2)

AGENTS OF CROSS POLLINATION

ENTOMOPHILY

Flowers which are pollinated by insects are called entomophilous flowers. The

characteristics of such flowers are as follows:

1) The flowers are large.

2) They are usually brightly colored to attract insects.

3) They usually emit scent to attract insects.

4) They produce nectar which is food for insects.

5) The pollen grains are sticky to be easily carried by insects.

6) The stigma is sticky.

7) The flowers tend to be in clusters to make them conspicuous especially in the case

where individual flowers are small for e.g. Dahlia.

ANEMOPHILY

Flowers which are pollinated by wind are called anemophilous flowers.e.g.Maize.

Characteristics of such flowers are as follows.

1) The flowers are small.

2) They are usually not brightly colored.

3) They do not produce scent or nectar.

4) Pollens are produced in large quantities.

5) Pollen grains are light, dry and smooth so that they can be easily carried away by

wind.

6) The stamens are long and hangout of the flower to be exposed to wind.

7) The anthers are large and loosely attached so that slightest wind may move them.

8) The stigmas are feathery and hang out of flower to trap pollen grains.

HYDROPHILY

Flowers which are pollinated by water are called hydrophilous flowers. They are found

only in aquatic plants.

Characteristics are as follows.

1) Pollen grains are produced in large numbers.

2) In some plants the pollen grains have gravity almost equal to that of water so that

they remain floating below the surface of water.

3) In some cases male flowers are such that they float on the surface of water till they

meet female flowers e.g. Vallisneria.

ORNITHOPHILY

Some flowers are pollinated by birds e.g. Bignonia,Canna

ELEPHOPHILY It is the pollination affected by Elephants .e.g. Rafflesia

ARTIFICAL POLLINATION

When man himself transfers pollen to stigma this is called artificial pollination.

FERTILIZATION

It is the fusion of nuclei of male gamete and female gamete.

The pollen grain is the male gamete.

The ovule inside the ovary is the female gamete.

The Pollen Grain

The mature pollen grain is a cell with a double wall i.e. Outer exine and inner intine.

Its nucleus is divided into tube nucleus and generative (male) nucleus.

The ovule Ovule is the inner part of ovary. Ovule becomes seed and ovary becomes fruit after

fertilization. Each ovule has one or two protective covering called integuments.

The integuments leave a small opening called micropyle whose function is that it is

meant for the entry of pollen tube.

Enclosed by the integument is the nucellus and further inside the nucellus is embryo sac.

The embryo sac contains seven (3+3+1) cells:

3 cells at micropylar end-1egg cell and 2 synergides

3 cell at opposite end called antipodal cells

1 large central cell containing two nuclei called polar nuclei.

GERMINATION OF POLLEN GRAIN

The pollen grain on falling on the stigma of same plant species is stimulated to germinate

due to release of sugars by stigma. The tube nucleus in the pollen grain directs the growth

of pollen tube and then it disintegrates. The generative nucleus divides into two male

gametes. The pollen tube grows through the stigma and style by dissolving the tissues

with the help of enzymes and reaches the ovary. Now the pollen tube releases its two

male gametes. One male gamete fuses with the egg cell to form zygote while the other

male gamete fuses with two polar nuclei in the central cell to form endosperm nucleus

(Triple Fusion).

DEFINITION OF DOUBLE FERTILIZATION

1) One male gamete fuses with the egg cell to form zygote.

2) The other male gamete fuses with two polar nuclei in the central cell to form

endosperm nucleus (Triple Fusion).

All together two fertilizations have occurred and hence termed as double

fertilization.

Assignment

1) Write Characteristics of Entomophilous flower.

2) Write Characteristics of Anemophilous flower.

3) Draw and label diagram of a mature pollen grain, pollen grain beginning to

germinate and pollen grain germinating on stigma where one pollen tube has

entered ovule.

4) Define the Following terms

1. Fertilization

2. Double fertilization

3. Triple fusion

Answer key of Biology Worksheet-3 1) It is the process of transference of pollen grains from the anther to the stigma.

2) There are two kinds of pollination: Self pollination and cross pollination.

3) Advantages of self pollination

It is much surer.

Parental characters are preserved.

No wastage of pollen grains.

The flowers need not to be large showy.

Scent and nectar need not to be produced by flowers.

Disadvantages of self pollination

Continued self pollination may lead to weakening of the variety or species.

The weaker characters of the variety cannot be eliminated.

It does not yield new varieties.

4) Advantages of cross pollination.

The offspring are healthier

The seed produced are abundant.

New varieties may be produced

Disadvantages of cross pollination.

It is not always certain.

There is lot o of wastage of pollen grains.

The process is uneconomical in the plant because the flowers have to be large,

colored, scented and nectar has to be produced.

5) Nature favors cross pollination

Some of the various devices or the conditions which favor cross pollination are as

follows:

Dichogamy

It means when anthers and stigma of the same flower mature at different times.

Unisexuality

The flowers may be either male or female and they may be present on separate

plants. In this way the crosspollination is the only possibility for e.g. Palm and

papaya

Self sterility

This is a condition in which even if the stigma receives pollen from the anthers of

the same flower, the pollen fails to undergo further growth.

Herkogamy

In some flowers the pollen of a flower cannot reach the stigma of the same flower

due to mechanical or structural barrier

Heterostyly In such flowers the stigma and anthers grow at different height which does not

favor self pollination.e.g.Oxali

Class 9 Commercial Studies Worksheet-2

BUSINESS ACTIVITIES

In the previous worksheet we learnt that there are two types of human activities—economic or commercial activities and non-economic or non-commercial activities.

Economic or commercial activities are of three types:

1.Business 2. Profession 3. Employment

MEANING AND DEFINITION OF BUSINESS:

Business is an economic activity. It involves sale,

transfer or exchange of goods and services with

the purpose of earning of money. It is the sum total

of those activities by which desirable things are

extracted from nature, transformed and processed

by man and machine, carried from place to place,

stored through times and placed in the hands of

those who are willing to pay for them.

In the words of James Stephenson: ―Economic activities performed for earning profits are

termed as Business‖.

Thus, Business may be defined as economic or commercial activity concerned with

production and distribution of goods and services with the purpose of earning profits. A

person engaged in business is known as businessman. The unit formed for carrying on

some business is called a business firm or enterprise.

CHARACTERISTICS (NATURE) OF BUSINESS ACTIVITY:

1. Sale, transfer or exchange: All business activity involves sale or exchange of goods

and services for some consideration. If there is no sale, transfer or exchange for price, it

will not be a business activity.

2. Dealings in goods and services: Every business enterprise produces or buys goods and

services for selling them to others. Goods may be consumer goods or producer goods. For

e.g. bread, cloth, shoes, machinery, insurance, banking etc.

3. Regular dealings: Business involves a series of dealings. A single transaction cannot be

called business. For instance, if a person sells his old scooter, it is not business. But if he

sells scooter on a regular basis, it will become a business.

4. Profit motive: The primary motive of business is to earn money and acquire wealth. A

business that does not earn profits cannot survive for long. Profits are also essential for

the growth and expansion of business.

5. Creation of utilities: A business makes goods more useful to satisfy human wants. It

adds time, place, form and possession utilities to various types of goods.

6. Economic activity: Business is primarily an economic activity as it involves production

and distribution of goods and services for the satisfaction of human wants. Business

maybe describes as a socio-economic function.

7. Risk: Risk is an essential part of business. In business, risk arises due to several

factors, e.g. changes in demand, theft, fire, natural calamities, bad debts, etc.

TYPES OF BUSINESS ACTIVITIES:

Business activities maybe broadly classified into two categories:

1. Industry 2. Commerce

MEANING AND TYPES OF INDUSTRY:

Industry means the production of products with the help of human beings and other

resources. It involves the application of men, machinery, materials, and money. Industry

refers to that part of business which produces want satisfying goods.

1. Primary industries:

Industries which are involved in the extraction and multiplication of natural resources are

known as primary industries. Primary Industries are of two types: Genetic and Extractive.

(A) Genetic industries: Genetic industries are engaged in the reproduction or

multiplication of certain species of plant and animals to earn profits from their sales.

Plant nurseries, poultry farms, cattle breeding farms and commercial kernels are some

examples of genetic industries.

(B) Extractive industries: These industries are engaged in the extraction of useful material

from beneath the surface of the earth and sea. In these industries, the products gifted by

nature are extracted and collected for the benefit of human beings. Agriculture, farming,

mining, fishing, forestry are the main examples of extractive industries.

2. Secondary industries:

The industries which are engaged in the conversion of the materials provided by the

primary industries are called secondary industries. For example the mining of iron ore

and coal is a primary industry. The conversion of these into steel is known as secondary

industry. Secondary industries are of two types: manufacturing and construction.

(A) Manufacturing industries: These industries are concerned with the processing or

transformation of raw materials and semi finished products into finished products. Such

industries change the shape and form of materials produced by Genetic and Extractive

industries . They create form utility by making products more useful to consumers. For

instance, the iron ore extracted through mining is converted into steel. E.g. cement, sugar,

textiles, fertilizers are the main examples of manufacturing industries.

(B) Construction industries: These industries are engaged in the construction of buildings,

bridges, roads, dams, etc. These industries create basic infrastructure for economic and

social development of the country through the process of fabrication.The distinctive

feature of these industries is that their prouducts remain fixed at one place and cannot be

taken physically to the market for sale.

3. Tertiary industries:

These industries are concerned with the provision of services to facilitate and assist the

primary and secondary industries. Transportation, warehousing, insurance, banking,

advertising and packaging are the examples of services provided by the tertiary

industries. These industries are collectively known as the service sector.

Q1. What is Genetic Industry.

Q2. What is Extractive Industry.

Q3.What is Construction industry.

Q4. Define Manufacturing Industry.

Q5. Classify the following into Extractive and Genetic Industry:

a) Poultry farm b) Plant nursery c) Animal Husbandry d) Agriculture

e) Fishing f) Mining g) Hunting h) Forestry

Q6. Mention the types of Utilities.

Q7. Define Industry.

Q8. Explain Profit Motive as a characteristic feature of business.

Answer key of Commercial Studies Worksheet-1

Ans:1 All human activities may broadly classified into two categories:

1. Economic or commercial activities

2. Non-economic or Non-Commercial activities

Ans:2 Commercial activities refers to all those activities which are undertaken to earn a

living and thereby satisfy human wants. The main objective of these activities are to earn

money and create wealth. e.g. a nurse working in the hospital.

Ans:3 The same activity may be commercial as well as non commercial. For example, a

nurse attending a patient in hospital is an economic activity as a nurse works for a salary.

But when the same nurse attends to her sick mother at home it is a non commercial

activity because the object is not to earn money. So, the activity of the same person may

be commercial at one time or place or non-commercial at another time or place.

Ans:4 Commercial activities are also known as occupations. Commercial activities or

occupations may be classified into three broad categories:

1. BUSINESS

2. PROFESSION

3. EMPLOYMENT

Ans:5 Business includes all those activities which are concerned with production and

exchange of goods and services with the object of earning profits. Business is an

economic activity because it is undertaken for earning money and producing wealth. The

person who are engaged in a business are known as businessman.

Ans:6 The term profession means an occupation which involves application of

specialised knowledge and skills to earn a living. The persons who are engaged in

profession are called professionals. They render personal services of a specialised nature

to their clients. Professionals receive fee for their services. Chartered Accountancy,

medicine, law or examples of professionals.

Ans:7 Economic activity is wherein people work for others and receive salaries and

wages for the services as per the terms and conditions of the agreement. Even

professionally qualified persons may work as employees. The persons who work for

others are called employees. The persons or organisations which engage others to work

for them are called employers.

Ans:8 Examples of economic or commercial activities

1. Production of goods by a manufacturer in a factory.

2. Distribution of goods by a wholesaler to retailer.

3. Clinic run by doctor.

Examples of Non economic activities:

1. Love and affection: for example taking dinner with the family cooking food for family.

2. Personal satisfaction: for example meditating in a park.

3. Physical needs: for example morning walk by a person.

Ans 9:

Ans10:

Class 9 Maths Worksheet-4

TOPIC: EXPANSIONS

Example 1: Simplify (a+b)2 – (a-b)

2

Steps: 1. Expand (a+b)2 and (a-b)

2 ; enclose them in brackets .

2. There is a negative sign before the bracket so change the sign of each term

of second expression while removing the bracket .

Solution: (a+b)2- (a-b)

2

=(a2+b

2+2ab) – (a

2+b

2-2ab)

=a2+b

2+2ab – a

2-b

2 +2ab

=a2 –a

2 + b

2 – b

2 +2ab +2ab

=4ab

Example 2: Simplify (𝟑𝒙 + 𝟏)𝟐 − 𝟑𝒙 + 𝟐 𝟑𝒙 − 𝟏 Steps: 1. Expand (3𝑥 + 1)2 using the identity (a+b)

2=a

2+b

2+2ab

2. find the product of ( 3𝑥 + 2) ((3𝑥 − 1) using either the identity

𝑥 + 𝑎 𝑥 + 𝑏 𝑜𝑟 by multiplication of binomial by binomial

3. Enclose the product within the brackets

4. While removing the brackets, change the signs because there is a negative

sign before bracket

Solution: (3𝑥 + 1)2 – 3𝑥 + 2 (3𝑥 − 1)

= 3𝑥 2 + 12 + 2 3𝑥 1 − 3𝑥 2 + 2 − 1 3𝑥 + (2 × −1)]

= 9𝑥2 + 1 + 6𝑥 − (9𝑥2 + 3𝑥 − 2)

= 9𝑥2 + 1 + 6𝑥 − 9𝑥2 − 3𝑥 + 2

= 3𝑥 + 3 = 3(𝑥 + 1)

Example 3 : If a + b =7 and a b =10 find the value of (a-b)

Steps: 1. Find the value of a2+b2

2. Now substitute the value of a2+ b2 in the identity of (a + b)2

Solution: a + b =7

(a + b)2 =72 (on squaring both sides)

a2+b2+2ab =49

a2+b2+2x10 =49 (on substituting a b =10)

a2+b2 = 49 -20

a2+b2 =29

now , (a –b)2=a2+b2-2ab

(a –b)2 = 29 -2x10 = 9

(𝑎 + 𝑏)2 = 9

a –b = ±3

Example 4: If (𝒙 − 𝟏𝒙) = 𝟒 , find the values of (i) 𝒙𝟐 +𝟏𝒙𝟐 𝒊𝒊 (𝒙𝟒 +

𝟏𝒙𝟒)

𝒊𝒊𝒊 𝒙 +𝟏𝒙 (𝒊𝒗)(𝒙𝟐 − 𝟏𝒙𝟐)

Solution: (i) 𝑥 − 1𝑥 = 4 (on squaring both sides)

(𝑥 − 1𝑥)2 = 42

𝑥2 +1𝑥2− 2 = 16

𝑥2 +1𝑥2

= 16 + 2

𝑥2 +1𝑥2

= 18 ------------------------Equation(1)

(𝑖𝑖) 𝑥2 +1𝑥2

= 18

( 𝑥2 +1𝑥2

)2 = (18)2 (on squaring both sides)

(𝑥2)2 + (1𝑥2

)2 + 2(𝑥)2 1𝑥2 = 324

𝑥4 +1𝑥4

+ 2 = 324

𝑥4 +1𝑥4

= 324 − 2

𝑥4 +1𝑥4

= 322

𝑖𝑖𝑖 (𝑥 +1𝑥)2 = 𝑥2 +

1𝑥2+ 2

= 18+2 [𝑶𝒏 𝑺𝒖𝒃𝒔𝒕𝒊𝒕𝒖𝒕𝒊𝒏𝒈 𝒙𝟐 +𝟏𝒙𝟐 = 𝟏𝟖 𝒇𝒓𝒐𝒎 𝑬𝒒𝒏(𝒊)]

= 20

𝑇𝑎𝑘𝑖𝑛𝑔 𝑆𝑞𝑢𝑎𝑟𝑒 𝑅𝑜𝑜𝑡 𝑜𝑛 𝑏𝑜𝑡𝑕 𝑠𝑖𝑑𝑒𝑠

(𝑥 +1𝑥)2 = 20

𝑥 +1𝑥 = ± 2 × 2 × (5)

𝑥 +1𝑥 = ±2 5

𝑖𝑣 𝑥2 − 1𝑥2= (𝑥+

1𝑥))(𝑥 − 1𝑥) using 𝒂𝟐 − 𝒃𝟐 = 𝒂 + 𝒃 𝒂 − 𝒃

𝑥2 − 1𝑥2= 4 × 2 5

𝑥2 − 1𝑥2= 8 5

Example 5: Using identities , evaluate

(i) (137)2 (ii) ( 992)

2

Solution: (i) (137)2= (130+7)

2

= (130)2+7

2+2(130) (7) using (a +b)

2=a

2+b

2+2ab

=16900 + 49 + 1820

=16949 +1820 =18769

(ii) ( 992)2 = (1000 – 8)

2

= (1000)2 + 8

2 – 2(1000) (8) using (a-b)

2 = a

2 + b

2 - 2ab

= 1000000 + 64 – 16000

= 1000064 – 16000

= 984064

Questions for practice

1. Simplify (i) (a +b)2+ (a –b)2 (ii) ( 5a +3b)2 – (5a -3b)2 -60ab

2. If 𝑥 − 𝑦 = 5 𝑎𝑛𝑑 𝑥𝑦 = 24 ,𝑓𝑖𝑛𝑑 𝑡𝑕𝑒 𝑣𝑎𝑙𝑢𝑒 𝑜𝑓 𝑥 + 𝑦

3. If 3𝑎 + 4𝑏 = 16 𝑎𝑛𝑑 𝑎𝑏 = 4,𝑓𝑖𝑛𝑑 𝑡𝑕𝑒 𝑣𝑎𝑙𝑢𝑒 𝑜𝑓 (9𝑎2 + 16𝑏2)

4. If 𝑥 +1𝑥 = 5 𝑓𝑖𝑛𝑑 𝑡𝑕𝑒 𝑣𝑎𝑙𝑢𝑒𝑠 𝑜𝑓 𝑖 𝑥2 +

1𝑥2 𝑖𝑖 𝑥4 +

1𝑥4

5. 𝐼𝑓 𝑥 − 1𝑥 = 3, 𝑓𝑖𝑛𝑑 𝑖 𝑥2 +1𝑥2

𝑖𝑖 𝑥4 +1𝑥4

𝑖𝑖𝑖 𝑥 +1𝑥 𝑖𝑣 𝑥2 − 1𝑥2

6. 𝐼𝑓 𝑥 +1𝑥 = 6 ,𝑓𝑖𝑛𝑑 𝑡𝑕𝑒 𝑣𝑎𝑙𝑢𝑒 𝑜𝑓 𝑖 𝑥 − 1𝑥 𝑖𝑖 𝑥2 − 1𝑥2

7. 𝐼𝑓 𝑥 − 1𝑥 = 8,𝑓𝑖𝑛𝑑 𝑡𝑕𝑒 𝑣𝑎𝑙𝑢𝑒 𝑜𝑓 𝑖 𝑥 +1𝑥 𝑖𝑖 𝑥2 − 1𝑥2

8. Using identities, evaluate (i) (1008)2 (ii) (97)2 (iii) (11.6)2

(iv) (9.98)2 [Hint ( 9.98)2= (10 - 0.02)2]

Answers of Maths Worksheet-3

1(i) 9𝑥2 + 100𝑦2 + 60𝑥𝑦 (ii)4𝑥2 +1

9𝑥2+

4

3

(iii)36 +25𝑥2

+60𝑥 𝑖𝑣 3𝑎2 + 2𝑏2 + 2 6 𝑎𝑏

2(i)9𝑎2 + 49𝑏2 − 42𝑎𝑏 𝑖𝑖 9𝑎2

4𝑏2+

4𝑏2

9𝑎2− 2

(iii)𝑎4 +𝑏2

4− 𝑎2𝑏

3(i) 𝑎2 + 4𝑏2 + 9𝑐2 + 4𝑎𝑏 + 12𝑏𝑐 + 6𝑐𝑎

(ii)36 + 4𝑦2 + 16𝑧2 − 24𝑦 − 16𝑦𝑧 + 48𝑧

4(i) 4𝑥2

9+

9

4𝑦2+ 4 +

2𝑥𝑦 − 6𝑦 − 8𝑥3

(ii) 4𝑥2 +9𝑥2

+ 13 − 6𝑥 − 4𝑥

5(i) 𝑎2 + 5𝑎 − 104

(ii) 9 − 9𝑎 − 28𝑎2

6(i) 𝑥4 − 𝑦4

(ii) 16𝑎4 − 1

81

……………………………………………………………………………………………

Class 9 Economics Worksheet-2

Read the following carefully learn and write the answers to the questions.

The English word economics is a derivative from the Greek word „Oikonomous‟. „Oikos‟ means household and „nomous‟ means management. Hence, simple definition and meaning of economics is “management of households”. The meaning of word “Economics” in Indian thought is “Arthashashtra”. The Sanskrit word “Arth” meaning purpose or goal and “Shashtra” means science. Thus, the meaning of Arthashashtra is “the science of benefits or purpose in practical life”

Definitions and Meaning of Economics by different Economists: Here are some definitions and meaning of economics by various well-known economists:

Economics definition of Adam Smith, [Wealth definition]

Adam Smith is known as ‗Father of Economics‟. In this definition, attention was only paid to wealth

as if wealth was everything and attention to mankind

was very little. In his book –An enquiry into the nature

and causes of wealth of nations (1976).

He defined economics as the science of wealth. That means

economics studies production and consumption of wealth.

According to him economics is a subject which tells us how to

make a nation wealthy .He assumes that the wealthier a nation

becomes the happier are its citizens. In his view wealth refers to gold, silver, land,

buildings and the whole production of goods and services that can be consumed. He

defined Economics as ―Economics is the study of the nature and causes of wealth of nations”. Economics is concerned with the study of wealth only.

Features of Adam smith‟s definition.

(1) Study of wealth-Economics only studies wealth.

(2) Study of material goods only-The term wealth has been used only for material goods

which are scarce and useful like table ,chair, book, pen.etc

(3) Economic man- Wealth definition lays emphasis on the man who does all activities

of his self interest. Such a man motivated by self interest is called Economic man.

Economics definition by Lionel Robbins, [Choice or Scarcity definition]

In 1931, Lionel Robbins in his book,

―Nature and Significance of Economics‖ gave the

following definition:

“Economics is the science which studies human behavior

as a relationship between ends and scarce means which

have alternative uses”.

Human wants are unlimited and most wants keep on recurring. On the other hand,

resources which help in satisfying human wants are limited and have alternative uses.

Hence, economics must deal with the problem of allocation of scarce resources in the

satisfaction of human wants to the maximum possible extent.

According to Robbins, Economics is a positive science and does not prescribe ‗how things should be‘. It studies ‗how human beings behave‘ and does not deal with how they should ideally behave. Hence economics does not deal with norms and thus is not a

normative science.

Features of Robbins‟s definition: (1) Unlimited wants/ends:

Our ends or wants are unlimited. If one want is satisfied then other crops up and there are

some wants which one has to satisfy again and again. If our wants had been limited, no

economic problem would have arisen.

(2) Resources are limited:

Although our wants are unlimited, resources at disposal to meet them are scarce or

limited. If these resources or means had been unlimited then also no economic problem

would have arisen.

(3) Alternative uses of resources/ means:

Limited resources at disposal have alternative uses this

makes them more scarce and one has to choose between

the uses of resources.

Economics definition by Paul Samuelson,

[Growth and Development definition]

“Economics is the study of how People and society choose, with or without the use of money, to employ scarce productive resources which could have alternative uses, to

produce various commodities over time and distribute them for consumption now

and in the future among various people and groups of society”. Hence, Samuelson talks about choice, allocation of scarce resources and evaluation of

costs and benefits of doing so. He gave the above definition in his book ―Foundation of

Economic Analysis”, published in 1947. He feels that economics should also suggest

how the scarce means should be used to satisfy more wants and to attain higher standards.

Features of Samuelson‟s Definition-

(1) Efficient allocation of resources-Growth definition lays stress not only on

allocation of resources but also on their proper utilization. So more wants can be

satisfied.

(2) Growth of resources- Available resources should not only be used properly, but

efforts should be made to increase them.

(3) Solution to economic problems-Economics is not only concerned with

identification of economic problems but should also suggest ways and means to

solve them.

All definitions in a way commonly point out that economics studies human

behaviour, is positive in nature, adopts scientific methods and methodologies and

this it is a social science.

MICRO AND MACRO ECONOMICS The subject matter of economics is broadly divided into two parts-Micro economics and

Macro economics. These terms were coined by Prof. Ragnar Frisch in 1933.

MEANING OF MICROECONOMICS

The word ‗micro‘ has been derived from the Greek word ‗mikros‘ meaning small. It

deals with small parts of the economy.

Micro economics study the behaviour of small economic units of an economy like

individual consumer producers and resource owners (Factors of Production). In‘ MICRO‟ the letter ‘I‘ stands for individuals. Thus micro economics study the economic

behavior of an individual .Prices have their important effect on the decisions of the

individuals sometimes as a result micro economics is also called PRICE THEORY.

MEANING OF MACRO ECONOMICS Macro means aggregates or groups of entire economy. In ‗Macro‘ the letter „A‟ stands

for aggregates. Thus macroeconomics studies the aggregates of an economy or economy

as a whole. Example: Gross domestic product, Total employment , Aggregate demand

,Aggregate supply, General price level etc. It thus focuses on macroeconomics variables

that is why macroeconomics has also been called ―Aggregative Economics”

DISTINCTION BETWEEN MICROECONOMICS AND MACROECONOMICS

BASIS MICROECONOMICS MACROECONOMICS

MEANING Is the study of individual

economic units of an

economy such as a

consumer, a producer etc.

Is the study of an economy

as a whole and its

aggregates such as national

income, total consumption

,general price level etc.

SCOPE Is concerned with the

determination of relative

prices of goods individually.

Is concerned with

determination of aggregate

output and general price

level in the economy as a

whole.

TOOLS Demand and supply of a

particular commodity or

factors of production are the

main tools of micro

economics.

Aggregate demand and

aggregate supply of all

goods and services are the

main tools of macro

economics.

DEGREE OF

AGGREGATES

There is limited amount of

aggregation in

microeconomics.

There is high degree of

aggregation in

macroeconomics.

EXAMPLES OF MICROECONOMIC AND MACROECONOMIC STUDIES.

MICROECONOMIC STUDIES MACROECONOMIC STUDIES

Household Income. National Income.

Supply of a commodity. Aggregate supply of goods and services.

Price determination of a commodity or

service.

Determination of general price level.

Demand of a good or service in the market. Aggregate demand of goods and services in

an economy.

Producer‘s equilibrium. Economy‘s equilibrium.

Answer the following questions briefly.(Short- Answers) 1. Give Adam Smith‘s definition of economics?

2. Give Robbin‘s definition of economics?

3. Give Samuelson‘s definition of economics?

4. Define Microeconomics?

5. Define Macroeconomics?

6. Give two examples of Microeconomic studies?

7. Give two examples of Macroeconomic studies?

8. The term micro and macro economics are also known as. Give the other names?

Detailed Questions(Long-Answers)

9. Explain Scarcity Definition of Economics in detail?

10. Distinguish between Micro and Macro Economics?

------------------------------------------------------------------------------------------------------------ ANSWER KEY OF ECONOMICS WORKSHEET-1

Answers to the following questions:

1. What do you mean by Economic Activity ?

Ans:-Economic activities refer to those activities of human being which are related to money

or wealth. They relate to the Production, Consumption , Distribution and Exchange of goods

and services. Example: A person goes to office or to a shop to earn money.

2. Who is known as the father of Economics? Give the name of his famous book?

Ans:-Adam Smith is Known as the father of Economics. His famous book is - An enquiry

into the Nature and causes of wealth of nations (1976).

3. Define a Non Economic Activity?

Ans:- Non- Economic activities refers to those activities which are not concerned with

money or wealth. They have no economic aspect. Example: Recreational, Religious,

Charitable, Parental, Social and Political Activities.

4. Give the two Greek words with meanings from which the term Economics was originally

derived?

Ans:- The term Economics was originally derived from two Greek words`` oikos‘‘ which means `Household‘ and ``nomous‘‘ which means `Management‘. Thus it means management of a household using the limited funds.

5. Distinguish between economic and non- economic activities in detail?

Ans:- Distinction can be explained in detail through a table given below.

BASIS Economic Activities Non-Economic Activities

1.Objective Economic activities are performed to

earn money or wealth.

Non-Economic activities are

performed for pleasure love and

affection. These activities do not have

money aspect.

2.Types Production, consumption, distribution

and exchange.

Can be divided into social, political,

religious, charitable, parental and

recreational activities.

3.Purpose

These activities are done to satisfy a

material need.

These activities are done to get mental

or psychological satisfaction.

4. Scope These activities take place either

between employer and employee or

between supplier and consumer or

between professional and client.

These activities generally take place

between family members or between

social workers and those who are

being served by them.

6. Classify the following activities into economic and non economic -

(a)Selling newspapers by a student – ECONOMIC ACTIVITY

(b)Washing own car – NON-ECONOMIC ACTIVITY

(c) Dancing performance by a student - NON- ECONOMIC ACTIVITY

(d) Public speech by PM. Narendra Modi - NON- ECONOMIC ACTIVITY

(e)Pocket allowance by father to daughter- NON-ECONOMIC ACTIVITY

7. Define Utility?

Ans:-Utility means want satisfying power of a commodity.

8. Define the term Market?

Ans:- A place where buyers and sellers of commodities establish contact and they are

involved in buying and selling of goods.

9. Give the meaning of Economics?

Ans:- Meaning of Economics-Economics is a subject that studies the economic activities of

man.Generally economics is defined as a social science that studies economic activities.

10. Define Consumption?

Ans:- Consumption deals with use of goods and services for satisfaction of want directly. eg:

Eating food to satisfy the want of hunger.

Class 9 Physical Education Worksheet-2

Cricket

Dismissal of Batsman

1. Bowled: The bowler has hit the wicket with the ball and the wicket has ―broken‖ with at least one bail dislodged. If the ball hits the wicket without dislodging a bail

it is not out.

2. Caught: The batsman has hit the ball with his bat or with his hand and the ball has

been caught before it has touched the ground by a member of the fielding team.

3. Leg before Wicket (LBW): Leg before wicket is judged in the manner that when

the left leg of the right handed batsman comes in front of the ball which may be

hitting the stumps, then that situation can be termed as LBW. This rule is

introduced because the batsmen will try to cover the full stumps to avoid the bowl

to hit the stumps.

4. Run Out: A member of the fielding side has broken or ―put down‖ the wicket with the ball while a batsman was out of his ground; this usually occurs by means

of an accurate throw to the wicket while the batsmen are trying to make a run.

5. Stumped: It is similar to run out except it is done by the wicketkeeper after the

batsman has missed the bowled ball and has stepped out of his ground and is not

attempting to make a run.

6. Hit Wicket: A batsman is out hit wicket, if he dislodges one or both bails with his

bat, person, clothing or equipment in the act of hitting the ball, or when setting off

for a run.

7. Hit the ball twice: This is very unusual and was introduced as a safety measure to

counter dangerous play and protect the fielders. The batsman may legally play the

ball a second time only to stop the ball hitting the wicket after he has already

played it.

8. Obstructed the Field: Another unusual dismissal which tends to involve a

batsman knowingly getting in the way of a fielder.

9. Handled the ball: A batsman must not intentionally use his hand to protect his

wicket.

10. Timed out: Timed out usually means that the next batsman did not arrive within

three minutes of the previous one being dismissed.

In the vast majority of cases, it is the striker who is out when a dismissal occurs. If

the non-striker is dismissed it is usually by being run out, but he could also be

dismissed for obstructing the field, handling the ball or being timed out.

Terminology

Dolly catch: A very simple catch which is easily taken by a fielder.

Maiden over: A maiden over is that over in which the batsman is unable to make

run.

Bump Ball: A ball which is played off the bat almost instantly into the ground and

is caught by the fielder.

Ball tampering: The illegal action of changing the condition of the ball by

artificial means usually picking or lifting the seam of the ball or applying saliva or

sweat.

Hat Trick: When a bowler takes three wickets on three consecutive balls he is

said to have scored a hat trick.

Extra: Run not scored by the batsman but the run though byes, leg byes, no-balls

and wide balls. These runs are included in the scores of a team but not credited to

the batsman.

Rubber: In the series of International Test matches, a team, who wins more

matches than the other team, is called to have won the rubber.

Seam: Slightly raised band of stitches round a cricket ball which enables bowlers

to make it spin.

Spin: To twist the ball when bowling so that, on pitching it changes direction.

No Ball: A ball is called ―no ball‖ when either umpire considers that the bowler‘s delivery is not fair.

Dead Ball: If the ball, while in play, is hit by the batsman on to camera or its

cable.

Follow on: The side batting first and leading by 200 runs in a five days match,

150 runs in 3 day match, 100 runs in 2 day match and 75 runs in a one day match

can ask their opponents to follow their innings.

Power Play: It is the name of fielding restrictions in limited overs ant T-20

cricket.

Innings: One player‘s or team‘s turn to bat or bowl.

Beamer: It is a type of delivery in which the ball without bouncing, passes above

the batsman‘s waist height. This ball is often close to the head of the batsman and is thus dangerous.

Night Watchman: A lower order batsman sent in when the light is dimming to

play out the remaining overs of the day to protect more valuable batsman for the

next day‘s paly.

Overthrow: The scoring of extra runs due to an errant throw from a fielder.

Dot Ball: A delivery bowled without any scored off it, so called because it is

recorded in the score book with a single dot.

Century: A single score of at least 100 runs, a significant landmark of a batsman.

Nick: A faint edge off the bat.

Golden Duck: A dismissal from the first ball faced in a batsman‘s innings.

…………………………………………………………………………………

Class 9 Computer Application worksheet-2

Computing and Ethics

12.4 Protection Against Spam

Spams are unwanted bulk emails that come from unsolicited sources. Spams are generally

sent in large numbers for commercial advertising. In spamming, millions of copies of the

same message are sent to email users worldwide. Mostly titles of these messages are very

attractive and compel the receiver to read these messages. Spam is a serious security concern

as it can be used to deliver Trojan Horses, Viruses, Worms, Spyware, and organize targeted

phishing attacks.

Sometimes spam attackers keep sending bulk emails till the email server is out of disk

space/memory. This practice is known as Mail Bombing.

12.1.6 How to Identify a Spam

Here are some tips to identify a spam message:

Messages that do not include your email address in the TO: or CC: fields are common

forms of Spam.

Actual email address does not match the name displayed e.g. the name displayed on

the email is 'Amazon Customer Services' but the actual email id is

gotcha123@buzz.com

The links in the message are dubious, for example, www.micrasoft.com instead of

www.microsoft.com

The message contains poor spelling and grammar.

The message is asking for personal details, for example, your online banking

password or date of birth.

Asking you to complete an action which you didn't initiate, for example, 'click on a

link to complete your order'.

Messages with attractive titles may contain offensive language or links to websites

with inappropriate content.

12.1.7 Protection Against Spams

Here are some tips to protect yourself from the spam messages:

Delete emails from unknown sources.

Keep software and security patches up to date.

Do not buy anything advertised in a spam email.

Be careful about giving out your email address to strangers.

Install good anti-virus and spam filtering/blocking software.

If you suspect that an email is a spam, do not open it or click links in the email.

Consider disabling the email client's preview pane and reading emails in plain

text.

Reject all Instant Message requests from persons who are not in your contact list.

.

12.5 Software Piracy

Software Piracy refers to the theft of software through illegal copying of genuine

programs or counterfeiting and circulation of products, which are duplicate copies of the

original. Most retail software are licensed and meant for Only one user at a time, i.e., you

cannot make a of this software. purchasing licensed software means that you are actually

purchasing a license to use the software. Any use of this, software

beyond the scope of license would be a violation of the license.

12.1.8 Types of Software Piracy

software piracy can be of the following types:

1. Softlifting refers to purchasing a single licensed copy of the software and installing it

on 2veral computers contrary to the licensing terms. For example, sharing software with

friends, co-workers and others.

2. Online Uploading and Downloading means making unauthorized copies of the

copyrighted software available on the Internet.

3. Software Counterfeiting means illegally duplicating and selling copyrighted software

in a form, so that it may appear legitimate.

4. OEM (Original Equipment Manufacturer) Unbundling means selling the software

separately although it was intended to be bundled with a specific accompanying

hardware.

5. Hard Disk Loading refers to installing unauthorized copies of software on the hard

disks of personal computers. It benefits the end users to buy the hardware from a

particular hardware dealer, but proves to be a loss for the software developing company,

6. Renting means unauthorized selling of software for temporary use. For example,

someone is renting a counterfeit

CD or DVD.

ASSIGNMENT WORKSHEET - 2

Q1. What is spam ?

Q2. How can one protect against spam ?

Q3. What is software piracy?

Q4. Name types of software piracy.

Answer Key of Computer Application Worksheet-1 Q1.What do you understand by computing ethics?

ANS. Computing is a process of utilizing computers to complete a task.

Ethics is a system of moral principles that differentiates between good and bad practices.

Computer ethics involves the code of conduct to use Information Technology in a responsible

way. It fulfils the requirements of an individual User without manipulating or destroying the data

of any other user.

Q2. What are intellectual property rights explain briefly.

ANS. Intellectual Property (IP) is a term referring to legal property rights of a person over his/

her creations of mind, both artistic and commercial. Under Intellectual Property Rights law,

owners are granted certain exclusive rights to a variety of intangible assets, such as musical,

literary, and artistic works. These rights are also applicable in case of discoveries, inventions,

symbols, and designs.

Q3. Write short notes on

Trademark

ANS. A trademark is a word, phrase, symbol, and/or design that identifies and distinguishes the

goods and services of one company from those of another.

Patent

ANS. A patent is a right concerned with a new invention to manufacture the patented product or

to use the patented process.

Copyright.

ANS. A copyright is a right granted by the law to the creator for his/her original work. Here, the

rights regarding creating a copy of any product are reserved by the author or company.

Q4. What is data privacy? Name its types.

ANS. when personal information is collected, stored and

shared without the consent of the authorized person/business concerned.

TYPES:

Personal details

Healthcare records

Financial transactions or status

Criminal justice investigations and proceedings

Business and commercial transactions