IIProf. James Tobin

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Index

Introduction ……………………………………………….. 3

Lab Schedule ………………………………………….…….. 4

Rules for Entering the Laboratory ………………………….. 5

Laboratory Precautions ……………………………….…….. 6

Science Lab Equipment ………………………………….…...8

Lab Practice #1 ………………………………………..…….. 11

Lab Practice #2 ……………………………………..……….. 13

Lab Practice #3 ………………………………………..…….. 15

Lab Practice #4 ………………………………………..…….. 17

Lab Practice #5 …………………………………………….... 19

Lab Practice #6 …………………………………………….... 22

Lab Practice #7-8 ……………………………………………..24

Lab Practice #9 …………..………….……………………….. 26

Bibliography ………………………………………..……….. 28

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Introduction

Physics is the science of the natural world dealing with the fundamental constituents of the universe, the forces they exert on one another, and the results produced by these forces. Sometimes in modern physics a more sophisticated approach is taken that incorporates elements of the three areas listed above; it relates to the laws of symmetry and conservation, such as those pertaining to energy, charge, and parity.

Physicists study a wide range of physical phenomena spanning all length scales: from the subatomic particles from which all ordinary (i.e., baryonic) matter is made (particle physics) to the behavior of the material universe as a whole (cosmology).

While physics has a remarkably broad overview, it attempts only to describe those aspects of the world that can be dealt with by the scientific method. It is not concerned with issues that cannot be verified even in principle, such as those studied in metaphysics.

NATURE IS BALANCE

Prof. James Tobin

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Lab Schedule

Lab Practice # Date123456789

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COLEGIO VILLA RICA

HIGH SCHOOL

RULES FOR ENTERING THE LABORATORY AREA

I. - All students must wear a long, regulation lab coat with name embroidered and bring the lab manual to enter the laboratory. If any student does not comply to this, he or she will receive the corresponding disciplinary sanction.*

II.-Food or drinks are not allowed in the area.

III. - Discipline and order must be maintained within the laboratory.

IV. - Before beginning any labor, all material should be checked to verify its condition.

V. - Any student who breaks lab material will be required to replace it.

VI. - All instructions given by the lab instructor must be followed completely.

VII. - Check that all Bunsen burners are completely closed upon completing your lab work.

VIII. - All work areas should be clean before and after lab work is done.

IX. - No student is permitted to be in the laboratory without the authorization of the instructor.

X. - All students who do not comply with point number III of this set of rules will receive a discipline report and sanction. He or she will also lose the right to participate in laboratory studies for a month and the laboratory credit for that month.

*The first incidence will cause a warning for uniform. The second incidence will cause a warning for discipline. The third incidence will cause suspension for 1 day.

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Laboratory Precautions

To avoid unnecessary accidents, and to indicate the action to be taken

when an accident occurs, read very carefully the following:

Safety Equipment

There is an emergency shower in each laboratory. Use it when corrosive liquids have spilled over clothes and skin.

If clothing is on fire, get the victim to the floor. The victim should be rolled over and over to smother the flames. Use a blanket or a lab coat.

Know the location of the fire extinguishers in the laboratory. Read the directions for their operation.

Small fires in test tubes, beakers and others can usually be smothered by covering with a heat resistant material.

Chemical burns must be washed promptly and thoroughly with water. It is the first treatment for all kind of accidents in which corrosive chemicals have been spilled or splashed on skin surfaces.

When a chemical substance has been splashed into the eyes, an immediate action must be taken to prevent damage to the sensitive tissues of that organ. The victim should wash the eyes with water for at least ten minutes. Seek medical attention immediately.

If possible, safety glasses or goggles must be worn during an experiment.

Contact lenses won’t be permitted. Lab coats (buttoned) are necessary inside a laboratory. Use the

appropriate color: white.

Handling of Glassware

Accidents from the careless handling of glassware occur very frequently, however, they can be avoided observing the following rules:

before inserting a thermometer or glass tube into a stopper or rubber tube, be certain the hole is large enough to accommodate the glass, lubricate the glass and the rubber with glycerol, protect your hands by

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holding the stopper and the glass in towels, and grasp the glass close to the end that is to fit into the stopper and twist softly

Do not attempt to push or pull glass tubing or thermometers from rubber tubing, corks or stoppers which have become hardened. Cut the rubber or cork from the glass.

Do not try to force an oversized stopper into a flask or bottle. Try to use the proper size stopper always.

When a beaker is hot, use tongs and not your fingers. Never point test tubes at your neighbor or yourself when heating

substances.

Handling of Chemicals

All bottles containing chemicals should be labeled. Volatile liquids such as alcohol, ether or benzene, must never be

distilled or evaporated near an open flame. Keep them well closed.

Waste All laboratory waste must be put in an appropriate container to avoid

injuries to third persons. Paper towels, corks, rubber stoppers, filter papers, etc., can be put in the

regular garbage after they have been cleaned of all chemicals

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Science Lab EquipmentYou should know the name of each piece and its basic use.

For exact volume measurements of liquids. The pipette on the left is a Volumetric pipette. It has only one graduation for delivering one exact volume. Pipette on the right is a Mohr pipette. It has graduations for delivering any number of exact volumes.

Pipette There are several styles of fillers used to draw liquids into a pipette. Physics’ students use a standard pipette bulb, described in lab techniques below. Never draw a liquid into a pipette with your mouth.

      Pipette filler

Used in conjunction with a vacuum connection to a water faucet to speed up filtration.

Filter flask The Erlenmeyer flask is the most common flask in the physics’ lab. It is used to contain reaction solutions.

Erlenmeyer flask

The rounded bottom of the Florence flask makes it ideal for boiling liquids. It also makes this flask easy to tip over when sitting on the lab table.

Florence flask

The volumetric flask is used to make solutions. It has a precise graduation line in the neck of the flask. A solute is placed into the flask, then the solvent..

Volumetric flask

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Beakers are the most versatile glassware in the lab and can be used for just about anything. The volume graduations on beakers should be used only for "ballpark" estimates.

Beaker

Used to make accurate measurements of liquid volumes. The bumper ring on larger cylinders is to prevent breakage if tipped over. Keep it near the top.

Graduated cylinder

This dish is used to recover dissolved solids by evaporation. While it can be heated, it should not be used for "strong" heating.

Evaporating dish

A watch glass can be used like an evaporating dish for very small amounts of liquid. It can also be used to cover beakers.

Watch glass

When attached to the ring stand, this iron ring is used to support glassware above the lab table.

Support ring

When attached to the ring stand, this clamp is used to hold a large test tube or Florence flask above the lab table.

Utility clamp

Crucibles are used as a container when something requires "strong" heating.

Crucible and coverThese tongs are used for picking up crucibles and crucible covers only.

Crucible tongs

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Used as a support for beakers when placed across a support ring.

Wire gauzeUsed to light a lab burner. Not a toy noisemaker during lab.

Striker

Used to grind solids into powers.

Mortar and Pestle Used to hold test tubes for short periods of "gentle" heating.

Test tube holder

When lined with filter paper, used to filter suspended solids from a liquid.

Filter funnel Used for rinsing solids out of a container when filtering.

Wash bottle

Used to transfer solids from their original container to a scale for weighing.

Chemical spoonUsed to close hoses by pinching them together.

Hose clamps

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COLEGIO VILLA RICAHIGH SCHOOL

PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE # 1PROPERTIES OF LIQUIDS.

Previous investigation: Investigate cohesion and surface tension. What causes both.How are they similar? How are they different?

Objective: To identify certain properties of liquids like: cohesion, adhesion and capillarity.

General information: Every body is composed of molecules which are united by intermolecular forces. COHESION is the force that keeps the molecules of the same body united; ADHESION is the attraction that is produced among the molecules of two bodies that are formed of different substances. CAPILLARITY is the phenomenon that involves the rising and descending of liquids by way of the capillary tubes; they are named in this way because their inner diameter is compared to the thickness of a strand of hair. Capillarity exists because of the cohesion of a liquids´ molecules and their adhesion with the molecules that form the walls of the capillary tube.

Procedure No.1: (Cohesion and Adhesion)1.- Using your eye dropper, put a few drops of each of the liquids on every one of the solids. Observe their behavior.

2.- According to your observations, classify solids and liquids according to this criteria: list the liquids according to how much they made the solids wet.

3.- Mention in each one of the cases what force was the most dominant, cohesion or adhesion?

4.- Of the materials you have used, what liquid made the solids wetter? What solid became wet more easily?

5.- Pour each one of the liquids into the test tube, observe what is formed and draw it in your notebook. According to the shape of the figure classify the liquids in a list of decreasing cohesion forces.

Material: A small boardA medium sized glassA sheet of waxed paperA piece of cardboardWater, oil, alcohol, liquid creamSmall test tubeEye dropper

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Make all of the classifications that you are asked to do, and in each case mention the force that is the most dominant.

Procedure No.2: (Capillarity)1.- Introduce a capillary in a container with water. Permit it to absorb so that the water ascends through the capillary.

2.- Stop the absorption so that the liquid descends until it reaches its level of balance.

3.- Mark the height that the water reached in the capillary. Do the same thing with the capillaries that have a different diameter.

Material:2 capillary tubes of a different diameterLiquids that have different densities2 graduated cylindersA ruler

Answer the following:

1.- What is the relationship between the tube’s diameter and the height that the water reached in it?

2.- How can you explain this?

3.- Repeat the operation. Introduce the same capillary in different liquids. Is there a relationship between the liquid’s density and the height that it reached in the capillary tube?

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COLEGIO VILLA RICAHIGH SCHOOL

PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE # 2DENSITY.

Previous investigation: Investigate icebergs. What are they? How is it possible that they float?

Objective: To determine the density of certain substances.

General information: Density or specific mass is defined as the result of dividing the mass of a given substance between the volume it occupies. As a result the mathematical expression for density is: p = m / V where:

p = density

m= mass in kilograms (kg)

v= volume in m3

Density is a specific property of matter because its value allows us to identify one substance from another and its value does not depend on the quantity of the substance you have got.

Procedure:

1.- Determine the density of water. To determine it, measure the mass of the test tube (10 cubic cm.) you will be using in the experiment with the triple beam balance.2.- Add 10 cubic cm. of water and measure the mass of the test tube again; when you subtract the mass of the empty test tube, you will find the mass of the 10 cubic cm of water.3.- Write in the box the data for mass, volume and density of the water that was obtained with the experiment.4.- Determine the density of alcohol and oil, following the same procedure as you did for water. Write down the data and the values in the box.

Material: 10 cubic cm. test tubeWater, alcohol and oilTriple beam balanceCalculator

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Substance Mass Volume (cubic cm.) p = m/v (g/ cm3.)Water

AlcoholOil

OPERATIONS:

Draw a picture showing how water, oil, and alcohol would be in relation to each other if placed into the same container.

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COLEGIO VILLA RICAHIGH SCHOOL

PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE # 3PASCAL’S PRINCIPLE ANDARCHIMEDES´ PRINCIPLE.

Previous investigation: a) Investigate how density affects floatation. How is it possible for a steel ship to float in water if steel has a density of 7.8 g/ cm3 and water has a density of only 1 g/ cm 3 ?b) What does Pascal’s Principle state?c) What does Archimedes´ Principle state?

Objective: To test the internal pressure exerted on a closed container and to find the force that a body submerged in a liquid experiences.

MATERIAL:

1 Ice pick or large sewing needle 1 Pair of pliers 1 Bunsen burner 1 Plastic syringe 1 Piece of iron 1 spring scale 100 ml test tube Water

Procedure 1: Pascal’s Principle1. Heat the point of the ice pick in the flame of the Bunsen burner. Be sure to hold it with the pliers so you do not burn yourself and then use it to perforate the syringe 6 times along the lower part. Fig. A

2. Place water into the syringe. Apply pressure to the water in the syringe by pushing the plunger and observe the intensity with which the water exits each hole. Fig. B’.

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Fig. A Fig. B’

General information: If a body floats (not only in water, but in any other liquid) it is because it receives the action of a force that counters the weight. This force is called the buoyant force.Procedure 2: (Archimedes’ Principle)1.- Determine the weight of a body with the scale

2.-Place the piece of iron in a test tube filled with water, and establish its apparent weight.

3.- As it is necessary to know what the volume of the iron is, fill the test tube with water and write down the volume of the water; introduce the iron and write down the new volume, the difference in volume is the volume of the iron.

4.- Establish the lift that the iron submerged in water experiences using this relation: Apparent weight = real weight – buoyant force.

5.- Calculate the buoyant force using the formula: F B = V body x density of the liquid x gravity

COMPLETE THE OPERATIONS:Apparent weight: Volume of water: Volume of iron:Buoyant force:Compare the results that you obtained in both cases. Are they the same?

Based upon what you have observed, how would you describe the intensity of the water that exited each of the holes on the syringe?

Was Pascal’s Principle proven? Why?

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COLEGIO VILLA RICAHIGH SCHOOL

PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE # 4

HEAT AND TEMPERATURE.

Previous investigation: Investigate the three temperature scales. What is the similarity between Kelvin and degrees Celsius? Which is the best scale for the most accurate scientific investigation? Why? Objective: To distinguish the concepts of heat and temperature.

General information: Temperature is a measurement that is dependant on the body’s state: it depends of the body itself and the conditions it is placed in.Heat, however, is not a measurement that is dependant on the body’s state; it is a form of energy.

Procedure:

1.- Put together a device just as your professor will indicate .2.- Put 100 ml. of water at room temperature in the flask and submerge the bulb of the thermometer in the liquid, place it in such a way that it doesn’t touch the bottom of the container.3.- Light the Bunsen burner and take note of the temperature every 2 minutes, until the water boils; write down the results in the box.4.- Repeat the experiment, but this time put 200 ml. of water in the flask. Register the results.

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Material: Universal supportTweezers to hold the thermometer200 ml. flaskWatch or chronometerGraph paperLab thermometerBunsen lighterStand and asbestos cloth

Time(Minutes)Temperature(°C)

Time(Minutes)Temperature(°C)

Answer the following:

Is there a difference in the time that the water takes to boil in both cases?

What conclusions can you draw about the quantity of heat applied and the temperature obtained in each one of the cases?

Using graph paper, make a graph of the results of the two tables that you obtained.

Represent the points of each one of them with a different color, as well as the union lines between the points.

The initial point must be the same in the two cases.

What happens with the rest of the points?

In which of the two cases was the water heated faster?

What is this due to?

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COLEGIO VILLA RICAHIGH SCHOOL

PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE # 5WAYS TO TRANSMIT HEAT.

Previous investigation: Why does a piece of metal at room-temperature feel cooler to the touch than paper, wood, or cloth?What is the difference between a conductor and an insulator?

Objective: To identify the three ways in which heat is transmitted.

General information: The transmission of heat from the hottest bodies to the ones that are cooler is achieved in these 3 ways: conduction in solid bodies, convection in fluids such as liquid bodies and radiation in gases and vacuums.

Procedure: 1.- Make the following device: insert the copper rod in one of the extremes of the soap and lean the other end of the rod over a piece of cardboard. Stick the tacks with melted wax and heat the extreme of the copper rod , then observe what happens after a few minutes.

2.- Fill the small container with hot water that is tinted with ink and place it standing inside the graduated cylinder filled with cold water and observe the movement of the water.

3.- Paint half of the inner part of the can black and leave the other half as it was.

4.- With melted wax, stick two tacks to the outer part of the bottle, one on the black part and the other on the part that has not been painted.

5.- Place a lit candle in the can; observe it for several minutes to see what happens to the tacks and then touch with your fingers the two parts of the can.

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Material: Copper rod or wire (length: 30 cm.)A bar of soap, ½ white cardboard, metal tacks, Bunsen burner.A graduated cylinder, 250 ml. container, ring support, asbestos cloth, water, saw dust,.A small container with water that has been tinted by ink.A small empty can without a lid, a candle, black paint and a pencil.

Answer the following:

1.- Why don’t all the tacks fall at the same time in the first experiment?

2.- What do we call the type of heat transmission observed in experiment one?

3.- Where did the hot water that had ink move to in the second experiment?

4.- What do we call the type of heat transmission observed in the second experiment ?

5.- What tack fell first in the third experiment?

6.- What part of the can’s wall heated the most?

7.- What color are the bodies that absorb more heat?

8.-What part of the can’s wall reflected the heat?

9.- What do we call the type of heat transmission observed in the third experiment?

Underline the correct answer.

1.- In conduction, heat isn’t transmitted in:

a) Glassb) A vacuumc) Copperd) Wood

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2.- Winter clothes:

a) Retain air which is a bad heat conductorb) Reduce transpirationc) Give heat to the bodyd) Facilitate the transmission of heat.

3.- The currents of the oceans are explained by which type of heat transmission?

a) conductionb) convectionc) radiationd) diffusion

4.-In a thermos, the transmission of heat by conduction is avoided with:

a) a cork stopperb) the vacuum between its wallsc) the exterior walld) the silver walls

5.- Some scissors and a wooden ruler have the same temperature, but the scissors feel colder because:a) Wood is not as heavyb) They repel the heatc) Metal is a good heat conductord) They shine

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COLEGIO VILLA RICA

HIGH SCHOOL PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE # 6EXPANSION OF SOLIDS, LIQUIDS, AND GASES.

Previous investigation: Why is it advisable to place small gaps between the steel rails of a rail-road? Would you need more space in the gaps in an area of extreme temperatures? Why or why not?Why is it advisable to lower the pressure in the tires of your car before going on a long trip?

Objective: To prove the expansion of solids, liquids, and gases.

General information: Expansion is the increase in size of a body when heat is applied. The movement of molecules in liquids, solid or gases becomes more intense when it is heated, the molecules start to push each other and so they occupy more space and this causes the body to increase in volume. Solids expand less than liquids, while gases expand notably.

Material: A flaskA graduated cylinder (500 ml.)2 glass tubesRubber stopperSupport stand, wire fire guard, Bunsen burner, matches, needles, coins, tweezers, electrical tape, paper sheet, balloons.Metal sphere and ring

Procedure: 1.- Stick two needles in a match box in such a way that you can just insert a coin between them.2.- Using your tweezers heat a coin in the flame of the Bunsen burner for about 2 or 3 minutes.3.- Tilt the match box and slip the hot coin onto it checking to see if the coin can pass between the two needles.4.- Fill the flask with water, put the stopper with the glass tube and mark with a line the level of water in the tube. Place the flask in a container that has hot water and observe what happens in the glass tube.5.- Put a balloon over the mouth of a small glass and place this device in a container with hot water. Observe the balloon.6. Try to pass the metal sphere through the ring before heating it.7.Heat the metal ring and then attempt to pass the sphere through it.

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Answer the following:

a) Did the coin pass through? ____________

b) Why? __________________

c) What did you observe in the tube as the flask heated?___________________

d) Why?__________________

e) What caused the balloon to inflate a little?__________________________

Complete the following sentences.

1.- When a solid body, liquid or gas is heated, the kinetic energy of its molecules:_____________________2.- The physical state in which a body’s molecules have more kinetic energy is:________________________

3.- The expansion or increase in volume of a body is due to the fact that the intermolecular spaces:__________________________________

4.- The kinetic energy of a solid body, compared to a liquid or a gas is:_______________________________

DRAWINGS:

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COLEGIO VILLA RICAHIGH SCHOOL

PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE #7-8: PARALLEL AND SERIES CIRCUITS

OBJECTIVE: To build series and parallel circuits.

PRIOR INVESTIGATION > Electrical current is:D.C. current is:Amp meters are used to measure:Electric current that changes its direction 60 times every second and is used in houses, factories and shops is _____________________ current.What unit is used to measure intensity of electric current?How many electrons are in a Coulomb?The flow of one Coulomb per second at a specific point in a conductor:Difference in potential is also known as_____________________Unit for measuring difference in potential:Define electrical resistance:

GENERAL: Ohms law states that voltage (V) in a circuit is proportional to the currents intensity (I) and to the total resistance in the circuit (R). This law can be expressed in the following way:

V = R x IIn a series circuit, the total resistance is the sum of the individual resistances:

Rt = R1 + R2 + R3 +…+ RnIn a parallel circuit, the total resistance is the sum of the individual resistances inversed:

Rt = 1____________ 1/R1 + 1/R2 + 1/R3 +…+ 1/Rn)

PROCEDURE:

1. - Mark with a letter (A, B, C, D, E, F, G, H) each terminal of the 4 bases of the bulbs.

2.- Cut 5 pieces of wire that measures 25 cm each; connect the negative pole of the battery to the terminal marked with letter A.

3. – Connect the B terminal with C, the D with E and so on until the all bulbs are connected and then connect the end of the H terminal with the positive pole of the battery.

4. - Connect the B terminal to the negative pole. Measure the current and voltage at different points the circuit using the multimeter. Loosen a bulb from the circuit and observe what happens.

5. - Connect the negative pole of the battery with terminal A. Make the connections A-C, C-E, F-G, H-D, D-B and the B terminal with the positive pole of the battery as shown:

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MATERIAL:4 light bulbs with a base2 m of wire of wire (no. 22 gauge)Needle nose pliersElectrical tape1 battery (9 V)1 voltage meter

OBSERVATIONS

1. - Write down the required values to calculate the intensity of flow (current) and the total resistance of each electrical circuit.

2. - Describe how you would calculate the intensity of flow (current) in the series circuit.

3.How would you compare the intensity of each light bulb in a series circuit of 4 bulbs that has a voltage of 120 volts to that of each bulb in a series circuit of 8 bulbs also with a voltage of 120 volts? Every bulb is 6 watts.

CHOOSE THE RIGHT OPTION TO EACH SENTENCE:

1. - In a series circuit, when a light bulb is loosened:a) The circuit is opened and there is no current

b) The current is the samec) The total resistance value raises and the current value goes downd) The total resistance goes down and the current rises

2. - In a parallel circuit, if a light bulb is loosened:a) The total resistance goes up and the current goes up toob) The total resistance goes down and the current goes downc) The circuit is opened and there is no currentd) Only that part in the circuit is altered

3. - In a series circuit, the sum of the voltage drop:a) Is 1b) Is 0c) Not knownd) Equal to the voltage applied to the circuit

4. – The voltage in each light bulb in a parallel circuit is: a) always the same as the other bulbs

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b) always different, depending on their location c) Sometimes the same d) impossible to say without further information

COLEGIO VILLA RICAHIGH SCHOOL

PHYSICS LABORATORY

Name:_________________________________ Date:__________________ Group:___________________

LAB PRACTICE #9: POLES AND MAGNETIC LINES

OBJECTIVE: To identify the poles and the lines of a magnetic field.

PRIOR INVESTIGATION > Define the magnetic field of a magnet:What is magnetism?How is an aurora borealis formed?Magnets can loose their magnetism due to:

GENERAL INFORMATION: Magnets are bodies that have the property of attracting iron, nickel, cobalt and their alloys. Magnets can be natural or artificial (man made).

The property that magnets have of attracting objects is concentrated in the zones called poles: North Pole and South Pole. Magnets apply attracting and repelling forces.Equal poles are repelled and opposite ones are attracted.

Around a magnet exists a field of forces called magnetic fields. It’s possible to magnetize a small body made of iron or steel by rubbing it several times in the same direction with a magnet. The property of the magnetic field is used in compasses for its orientation towards the planets north pole.

PROCEDURE #1:

1. - Place a sheet of glass over 2 piles of books. Place the iron filings on top of the glass. Bring a bar magnet close to the lower face of the glass, and watch the lines of the magnetic field.

2. - Repeat the previous step with different magnets; place the magnetic poles using different combinations and observe the lines of the magnetic field that are formed.

3. - Draw a piece of paper a face or other picture, and on top of it place the iron filings (for example, in the shape of a hair, eye brows, mustaches, beards). Put the magnet on the lower face of the glass under the drawing and observe.

4. - Bring together one of the magnets with the objects that you obtained and then complete the table.

5. - Magnetize the needle, put it inside the cork, place it on a container with water and observe its behavior. Bring the magnets close in different positions and watch the compass’ behavior.

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MATERIAL:1 glass that measures 30x30 cm with tape on its edgesDifferent objects (pen, pencil, cork, etc)4 magnets (2 bar type and 2 horse shoe types)4 books1 white sheet of paper1 needle1 cork stopper1 water recipient

OBSERVATIONS:Draw the magnetic field lines, formed by the different types of magnets.

QUESTIONS:1. - Why do the iron filings help to observe the magnetic field lines?

2. - Why does the needle always point in a certain direction?

COMPLETE:

Objects attracted by magnets Objects not attracted by magnets

CHOOSE THE RIGHT OPTION:

1. - Where you find more iron filings means that the magnetic field is:a) weakb) Strongc) No changed) Same

2.- If you put 2 north poles together from 2 different magnets, the magnetic field is the zone that:a) Cancelsb) Fortifiesc) Weakensd) Saturates

3. - When you place a magnetized needle in the water recipient, the north pole of the needle points towards the:

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a) Northb) Southc) Eastd) West

Bibliography

Cromer, Alan “Physics for Life Science” York McGraw-Hill 1974

Dispazio-Lisowski-Skoog “Science Sights” California Addison-Wesley Pub-Comp. 1979

Burdett, Silver and Ginn “Physical Science” Morristown N.J. 1990

Thompson, McLaughlin, Smith “Merrill Physical Science” Glencoe-McGraw-Hill Pub. New York 1995

Hewitt, Paul G. “Conceptual Physics” California Addison-Wesley Comp. 1997

Hewitt-Suchocki-Hewitt. “Conceptual Physical Science” AddisonWesley San Francisco 2004

Zitzewitz-Elliot-Hasse “Physics- Principles and Problems” New York, McGraw-Hill 2005

Wikipedia www.wikipedia.org.

The Physics Classroom www.glenbrook.K12 .il.us/gbssci/phys/class/BBoard.html

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