cxc physics lab

5/25/2018 cxc Physics lab

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TABLE OF CONTENTS

SBA

Exp

t.

No

TITLE EXPERIMENT SKILL PAGE

NO

1 Physical Measurements

and Units Finding volume of a Jamaican $20 coinby two different methods O/R/R/MM 2


and Units Finding the area of a leaf O/R/RA/I


and Units Finding the density an irregular object


and Units

The effect of length on the period of a

pendulum

A/I


and Units

The effect of mass of the weight on the

period of a pendulum

PD

6 MECHANICS Finding the centre of gravity of anirregular object

MM

7 MECHANICS Finding the weight of the meter rule8 MECHANICS Verifying Hookes Law

9 Thermal Physics and

Kinetic energy Finding specific heat capacity of a metal


Kinetic energyFinding specific heat capacity of

concrete

PD


Kinetic energyFinding the latent heat of fusion of ice


Kinetic energy

Verifying Boyles law A/I


Kinetic energy

Verifying Charless law O/R/R

14 Waves and Light Investigating the relationship between

incident light and reflection

M/M

15 Waves and Light Finding focal length of a convex lens M/M

16 Electricity and

MagnetismInvestigating the relationship between change

in the lengthof a wire and resistance

A/I/ O/R/R


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17 Electricity and

Magnetism Investigating the relationship between changein the thicknessof a wire and resistance PD

18 Electricity and

Magnetism

Investigating the voltage characteristic of a

lamp

19 Physics of the atom Effect of distance (from the detector) on thetransmission of beta radiation

20 Physics of the atom Effect of shielding materials on the

transmission of beta radiation

PD


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EXPERIMENT 1TITLE: MEASUREMENTSAIM: Finding volume of a Jamaican $20 coin by two different methodsDATE:Apparatus and Mater ials

Jamaican $20.00 coin (5)

Vernier Caliper

100 cm3measuring cylinder

Pipe water

Procedure

VOLUME FROM CALCULATIONS USING THE VERNIER CALIPER

1. The caliper was checked to ensure that when it is closed the readings at zero (0)

2. The diameter of the $20 coin was measured and recorded.

3. The thickness of the same coin was measured and recorded.

4. The formula for volume of a cylinder was used, (4r2h), where h is the thickness

of the coin.

5. The volume of the $20 coin was calculated.

Results

Diameter of 20 coin 22.5mm 2.25cmThickness of 20 coin 0.25cm 0.250cmRadius the 20 coin 11.25mm 1.13cmTABLE SHOWING RESULTS FOR METHOD 1


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Calculations for method 1

The volume of the Jamaican 20 coin is 1.34cm3VOLUME FROM DISPLACEMENT USING THE 100ml MEASURINGCYLINDER

1. 50 ml of pipe water was accurately measured into the measuring cylinder.

The value was recorded in a suitable table

2. Five (5) $20 coins were added to the volume in the measuring cylinder.

3. A new volume was recorded when all the coins were in the measuring cylinder.

4. The net volume was determined and the volume divided by five (5) to the

Average of one $20 coin.

Results

olume

Volume of waterVolume of 5 coinNet volume

100ml105ml5ml

TABLE SHOWING RESLUTS FOR METHOD 2


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Calculations for method 2

Net volume = V2 - V1

= 105100

Net volume = 5ml

Average volume of one coin

Net volume = 5 ml = 1 ml

5 5

Average volume = 1ml

Discussion

Both results were the same, this suggest that the experimenter had carried out theexperiment with no error .

Precautions /Possible sour ces of errors

Ensure Vernier caliper is set at 0 Ensure measuring cylinder is on a flat surface

Ensure to avoid paradox errors

Conclusion

This experiment has proven that the volume of the Jamaican $20 is 1.00cm3,using both the

Vernier caliper method and the measuring cylinder method.


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EXPERIMENT #2

TITLE: MASUREMENTSAIM: To find the area of a suitable leaf using a graph paperDATE:

Apparatus and Mater ials

Graph paper

pencil

suitable size leaf

Procedure

1. A suitable leaf was used, that covered two thirds of the graph paper.

2. The leaf was positioned on the paper, held down firmly and the edges were traced

around with a sharp pencil.

3. The graph paper was used to determine the size of the area of the leaf

4. The largest square are 2cm 2cm =4 cm2 , the next smaller squares are 1 cm

1cm2 and the smallest square is 2mm 2mm =0.04cm2

5. The largest squares were labelled A and were counted and multiplied by 4

Cm2

6. The smaller squares were labelled B and were counted and multiplied by

1cm2

7. The smallest squares were labelled C and were counted and multiplied by

0.04m2

8. The areas were recorded and added up to get the total area of the leaf


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Calculations

No. of A squares = 22 4cm2 = 88 cm2

No. of B squares = 23 1cm2 = 23 cm2

No. of C squares = 453 0.04cm2 = 18.12 cm2

Total area of leaf = 129.12 cm2

Precautions

Ensure leaf does not shift

Conclusion

Based on the experiment done it was proven that the area of a suitable leaf is 129.12cm2


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EXPERIMENT 3TITLE: MEASUREMENTSAIM: To find the density of an irregular object using Archimedes principleDATE:Apparatus and Mater ials

100 ml measuring cylinder

Small stone (that can easily fit inside the measuring cylinder)

Pipe water

Triple beam balance or electronic balance

Tissue or hand towel

Procedure

1. The scale was set up and checked to ensure that it is at zero.

2. The mass of the stone was Weighed and recorded.

3. 50ml of water was measured in the measuring cylinder.

4. This was recorded as the initial volume of water.

5. The measuring cylinder was tilted to about 45and a small stone was rolled downthe sides without splashing. It was placed on a levelled surface; the new volume wasnoted and recorded.

6. This was recorded as the final volume of the water.

Calculations

Initial Volume of water =50 ml

Final volume of water =70.1ml

Net volume =

Net volume = V2 - V1

= 70.1ml50ml

Net volume = 20.1ml


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Density P=mass/volume

=23.9g/20.1ml

=1.19g/ml

Precautions

Ensure that meniscus is read from eye level

Conclusion

Based on the experiment done, it can be concluded that the density of an irregular

shaped object is 1.19g/ml using Archimedes principle.


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EXPERIMENT 4: TITLE: MEASUREMENTSAIM: To study how the length of a string affects the period of a pendulumDATE:


A 60100 cm crochet cord or any other suitable string

A 100g/200g weight

Dark coloured marker

Meter ruler

Protractor

Procedure

1. The crochet cord was tied to the weight.90cm between the top of the weight

and fingers.

2. A position was marked 5cm down from the top of the cord with a marker.

This was treated as the 85cm position.

3.10cm position were accurately marked from this position down towards the

weight.

4. Then the cord was held vertically, then a protractor was used to ensure it is

at the 90mark.

5. A stop watch was used to time the oscillations, the stop watch was checked to

ensure that it is at 0.

6. The cord was displaced by 50and released, ten oscillations were counted at

length.

7. The cord was held at the 75cm position. Procedure five was repeated until it

has reached the 45cm position.


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8. The results were recorded in a suitable table

Results

TABLE SHOWING RESULTS

Discussion

When length is changed it will take more or less time to oscillate, depending on its length

and acceleration due to gravity. Therefore, the period may be varied by changing either two

factors .Since acceleration due to gravity is constant on Earth; the only dependent factor is

the length of the pendulum. As the length decreases the period becomes faster.

Precautions

Ensure that your eye is level with the centre of the bob when measuring length to

avoid parallax error Ensure that the pendulum swings in one plane only - avoid circular movements

Length(cm) Period10oscillationOneOscillation(period/10)

T2 AngleOfdisplacementMassof thebob

85 20.10 2.01 50 250

75 18.82 1.882 50 250

65 17.92 1.792 50 250

55 17.19 1.719 50 250

45 16.05 1.605 50 250


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Conclusions

Based on the experiment done it can be concluded that a pendulum will exhibit a period

that varies depending on its length, as the length decreases the period

becomes faster.


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EXPERIMENT 5:TITLE: MEASUREMENTSSKILL: P & D

DATE:

Hypothesis:The mass of the pendulum will affect the period of oscillation of the pendulumAim: To determine the effects of mass on the period of the pendulumProblem Statement: To plan an experiment to show how the mass of the pendulum affectsthe period of the pendulum

Apparatus and Mater ials:

20g,30g,40g,50g masses string

,ruler Compass retort stand

Clamp stop watch

Procedure

1. Measure the length of the string to be 20cm

2. Attach the 20g mass to the end of the 20cm string

3. Tie the pendulum onto a clamp attached to a retort stand

4. Place the protractor in your hand and check to ensure that the cord is at the 90

mark on the protractor

5. Displace the pendulum by 60,release and count ten oscillations, the stop watch

should be started simultaneously when the mass is released

6. Repeat the procedures two through five using different masses.7. Record your results in a table and plot a graph of mass against period


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Expected Results and Explanation

Variables

Manipulated

mass

Responding

Time taken for oscillations to occur

Control

Length of the pendulum

Number of oscillations

Displacement of the pendulum

Precautions

Ensure timer is set at zero

Ensure that your eye is level with the centre of the bob when measuring length toavoid parallax error

Ensure that the pendulum swings in one plane only - avoid circular movements

Length(cm) Period10oscillation

OneOscillation(period/10)

T2 AngleOfdisplacement

Massof thebob50cm 14.88 1.488 60 20g

50cm 15.06 1.506 60 30g

50cm 15.11 1.511 60 40g

50cm 15.24 1.524 60 50g


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EXPERIMENT 6TITLE: MEASUREMENTSAIM: To find the center of gravity of an irregular object

THEORY: The center of gravity of a body is defined as the point of application of thegravitational force due to the earths attraction on it, or the point on that body where all the weightseems to actApparatus:

An irregular shaped object (cardboard)

Bob

String

Nail or small screwdriver

Procedure

1. Three holes were punched as far as possible from each other, close to theedge of the irregularly shaped cardboard

2. The nail was inserted in a steady overhead board stand.

3. The object was placed over the nail and the loose end of the thread was tied

over the object onto the nail.

4. A pencil was used to mark the line where the string falls on the object.

5. The above steps were repeated for the other two holes.

Discussion

Center of gravity of an object is where all its weight seems to act. The position on thelamina where all lines intersect is called the center of gravity. The lamina was balanced at itsintersection point.

Precautions

Ensure that the string swings freely across the lamina Make sure the string come to rest before marking the positions


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Conclusion

The center of gravity of the lamina was determined by balancing the lamina at its

intersection point


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EXPERIMENT 7: Finding the weight of the meter ruleTITLE: MEASUREMENTSAIM: To find the weight of a meter ruler using the principle of moments


Meter rule (1)

100g mass

String

Pivot

Procedure

1. A string of approximately 30cm of length was tied to a 100g mass.

2. A loop was tied at the other end ,that allowed the string to be move with the 100g

mass along the length of the meter rule

3. The string was placed with 100g mass at the 5cm position on the meter ruler.

4. The meter rule was balanced on the pivot.23cm from the same end measured 5cm

5. This length was recorded as l cm and the distance from the 100g mass to the pivotas d cm ,this was recorded in a suitable table

6. This procedure was repeated with the string and mass at the 10cm mark and the

new values were recorded in the same table

7. This procedure was continued until the string and mass reached the 30cm mark.


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Results

Position of thepivot from thesame end (cm)Distance fromthe 100g mass tothe pivot d (cm)

Position of 100gmass from oneend l (cm)

23.5 18.5 5

26.7 16.7 10

29.8 14.8 15

32.7 12.7 2035.5 10.8 25

38.5 8.5 30

Precautions

Conclusion


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EXPERIMENT 8:TITLE: MEASUREMENTSAIM: To demonstrate that the extension of a spring is proportional to the applied weight aslong as the elastic limit of that spring is not surpassed.

Theory: Hookes law states that provide the elastic limit has not been exceeded the stretching forceon a spring is directly proportional to the extension of that spring. The extension is the differencebetween the natural length of that spring and the extended length due to the stretching force.

Apparatus and mater ials

Meter rule (1)

100, 50, 200g masses (two or three of each preferably)

String (50100cm long),

Spiral spring

Clamp

Set square

Procedure

1. The ruler was repositioned so that it was right against the spring that was used intest.

2. The reference line was moved to ensure that it lines up with one of the numbers onthe ruler. This mark was recorded in a table as the zero position mark.

3. The lowest mass (50g) was attached to a spring with the mouse and the extensionvalue was recorded in table.

4. Step 5 with the other known masses was repeated and the extension values were

recorded in the same table.5. A graph was plotted of force vs extension and then determined if Hookes law was

obeyed or not.


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Results

MASS (g) MASS (kg) Force (N) [Mass(kg) x 10] ZeroExtensionvalue (cm)Extension (cm)

50 0.05 0.5 0 5

100 0.1 1 0 10

150 0.15 1.5 0 24

200 0.2 2 0 32

250 0.25 2.5 0 44

300 0.300 3 0 50

350 0.350 3.5 0 62

Discussion

The force vs extension graph gives a straight line which shows that force is directlyproportional to its extension. The gradient of the force vs extension give spring constantwhere spring constant is how stiff or rigid the string is. The table also shows that as the

force increase the extension also increases .It was also observed that the graph obeyedHookes law

Precautions

Ensure that the string does not pass it elastic limit


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Conclusion

Base on the experiment done Hookes law was verified because force vs extension reflects a

straight line


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EXPERIMENT 9:TITLE: Thermal Physics and Kinetic energyAIM: To find the find the specific heat capacity of a metalSKILL:Theory: The specific heat capacity is the heat required to produce a unit temperature rise (1C) ina given unit mass of the substance (1kg or 1g). So by knowing the mass of the substance and thechange in temperature, the specific heat capacity of that substance can be evaluated experimentally.


Measuring cylinder

Bunsen burner o

100g mass

Small polystyrene cup (3) (8 or 12 ozs size)

Thermometer

400ml beaker (1)

Tripod stand (if using Bunsen burner)

String (1030 cm long)

Procedure

1. The string was tied to the 100g mass

2. Piped water was added to the 400ml beaker until it is between 1/2to 2/3full3. The Bunsen burner, gauze and tripod stand was set up and the 400ml beaker was

placed on top of it

4. The mass and string was placed into the 400ml beaker. The string was checked toensure that it was just barely hanging over the side and not touching or too near theheat source.


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5. The water was heated until it began to boil. Then it was allowed to boil gently for 5minutes. This temperature was recorded in a table

6. During this 5 minute period, 60ml of pipe water was accurately measured with themeasuring cylinder and transferred to each of the polystyrene cups.

7. The temperature of the water was measured in each of the cups. These temperaturevalues were recorded in a suitable table.

8. After the 5 minute period, the mass from the boiling water with the string wasremoved and was gently transferred to one of the polystyrene cups.

9. The mass was moved up and down within the mass of water in the cup and thehighest temperature increased on the thermometer was noted. This value wasrecorded in a table.

10.The mass was then returned to the boiling water and let for another 5 minutes. Themass was transferred to another polystyrene cup and the highest temperature wasnoted again. That value was noted in the same table.

11.The mass was then returned to the boiling water for the third time and theexperiment was repeated for the final time and the temperature value was recorded inthe same table

Results

Specific heat capacity of water = 4200 J Kg-1 C-1

Mass of water =60g

Temperature of water before =33c

Temperature of water after =39.8c

Mass of metal =100g

Temp of metal before =99 c


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Heat lost by metal = Heat gained by water

Calculations

m = is the mass of the substance (Kg) (water or 100g mass),

c = specific heat capacity (J Kg-1C-1) andT = temperature change (C)

m massx c massxT mass= m waterx c waterx T water

Mass of thermometer before = 401.1g

Mass of thermometer after =422g

Final temperature 39C

Mass of water

Precautions

Conclusion


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EXPERIMENT 10: Finding specific heat capacity of concreteTITLE: Thermal Physics and Kinetic energySKILL: P & DDATE:Aim: To plan an experiment to determine the specific heat capacity of concreteTHEORY: The specific heat capacity is the heat required to produce a unit temperature rise(1C) in a given unit mass of the substance (1kg or 1g). So by knowing the mass of thesubstance and the change in temperature, the specific heat capacity of that substance can beevaluated experimentally.


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EXPERIMENT 11: The latent heat of fusion of iceTITLE: Thermal Physics and Kinetic energyAIM: To find the latent heat of fusion of iceSKILL:Theory: The latent heat of fusion is the heat required to convert unit mass of ice at 0C to thesame mass of water at the same temperature. The same amount of heat is released when theprocess is reversed. This process occurs (in either direction) without a change in temperature. Orto say it in another way, the temperature does not increase or decrease, until the change of state iscompleted.The value of the latent heat of ice can be determined by completely melting small pieces of ice in aknown mass of water. The heat energy required to completely change the ice to liquid would begained from the surrounding water and so the latent heat of the ice can be deduced from thefollowing relationship:

Heat energy gained by the ice = Heat energy lost by the water

, micex lice+ m icex cwx Tice= mwaterx cwaterx Twater


Measuring cylinder

Small polystyrene cup (3) (8 or 12 ozs size)

Thermometer

Electronic balance or triple beam balance

ice

Method

1. The Styrofoam cup was weighed on the scale2. The water was warmed water to 70C3. About 60g of water was weighed in the Styrofoam cup4. The initial temperature of the water was measured and recorded.5. About 10g of ice was added into this water6. The mixture was stirred until the ice was completely melted.7. The new temperature was recorded8. The Styrofoam cup with the water/ice mixture was reweighed and the value

recorded.9. The weight of the ice added to the water was deduced .


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EXPERIMENT 12: Verifying Boyles lawTITLE: Thermal Physics and Kinetic energyAIM: To verify Boyles Law from experimental dataSKILL: A/ITheory: Boyles law states that the volume of a fixed mass of gas is inversely proportional to theapplied pressure at a constant temperature.

P1/Vor vice versa and consequently P = k/V or k = PV where k is a constant


Pressure gauge

A sealed tube with air or any other suitable gas

Method:

1. The default value on the system at the given temperature was noted and recorded inthe table.

2. The pressure was increased by defined amounts e.g. 20kPa or 20 atm on the systemand the corresponding change in volume noted.

3. The new values were recorded in the same table.4. This was repeated 5 more times, each time recording the pressure and volume values

in the table.

Results

Pressure Volume (ml) V15.8 32.6 1.6317.4 29.6 0.5720.0 25.7 0.05022.2 23.2 0.04523.8 21.6 0.42


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Discussion

Precautions

Conclusion


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EXPERIMENT 13: Verifying Charless lawTITLE: Thermal Physics and Kinetic energyAIM: To verify Charless law by experimental methodsSKILL: O/R/RTheory: Charless law states that the volume of a fixed mass of gas is directly proportional to thetemperature at a given pressure.

V T and consequently V = kT or k = V/T where k is a constant


Volume gauge

A sealed tube with air or any other suitable gas

Method:

1. The default pressure value on the system was noted and recorded in the table

2. The pressure was increased by defined amounts e.g. 10 or 20 C atm on the systemand the corresponding change in volume was noted.

3. The new values were recorded in the same table.4. This was repeated 56 more times, each time recording the temperature and

volume values in the table.

Results

Pressure Volume286.5 24.95296 26.00307 26.78320 27.91

340 29.166

Precautions


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Conclusion


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EXPERIMENT 14: Investigating the relationship between incident light and reflectionTITLE: Waves and LightAIM: To investigate the relationship between incident light and reflectionSKILL: M/MTheory: Reflection occurs when a wave hits a boundary and goes back into the medium withoutcrossing the boundary. The laws of reflection states that:

1. The angle of incidence is equal to the angle of reflection2. The incident ray, the reflected ray and the normal all lay in the same plane3. When reflection occurs the wavelength of that ray remains unchanged


Plane mirror

Common pins

Sharp pencil

Cardboard sheet (8 x 11) or bigger

Plain paper

Protractor

Small ruler (preferably clear plastic)

Method:

1. A protractor and ruler; were used to draw a horizontal line on the lower third of theplain paper. The paper was placed in the landscape position.

2. The protractor and pencil were used to draw a normal line in the center of thehorizontal line (broken lines).

3. A line was drawn 10from the normal4. Two pins were placed at different positions along this line.

5. The mirror was placed in line with the horizontal line so that the normal line was inthe center of the mirror

6. On the other side of the normal line, using the reflections in the mirror, the two otherpins were aligned so that they appeared as one in the reflection.

7. The pins were removed and a line was drawn through the pin holes. This representedthe reflected ray.


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8. The angle of the reflected ray was measured and both the incident and reflected ray

angles were recorded in a table

9. The procedure was repeated six more times each time increasing the angle by 10and

recording the results in the same table.


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EXPERIMENT 15: Finding focal length of a convex lensTITLE: Waves and LightAIM: To determine the focal length of a convex lensSKILL: M/MTheory: A convex lens is thicker in the middle than the edges. It has the ability to bring incidentparallel rays into a single focal point. This focal point can be determined from experiment.Apparatus and Mater ials:

Convex lens

Convex lens holder

Light source

White screen

Illuminated object (with a pin or a small mesh in the centre)

Meter ruler

Small ruler (preferably clear plastic)

Method:

1. A protractor and ruler; were used to draw a horizontal line on the lower third of the

plain paper. The paper was placed in landscape position.2. The apparatus was set up in a similar manner to the diagram. The image on the screen

was adjusted until a sharp image was seen.3. The distance of the illuminated object from the lens was recorded as uand the

distance of the image on the screen from the lens was recorded as v in a table4. The distanceuwas decreased by5cm and the screen was re-adjusted until the image

was again sharp. The v value was re- measured and bothuandv were recordedinthe table

5. This was repeated for four to five more times and the values were recorded in the

table.6. Using the equation: 1/u + 1/v = 1/f, the value of f was determined from values ofu and v in the table.


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Results

..u (cm) v (cm) 1/u (cm-1) 1/v (cm-1) 1/f (cm-1)

f (cm)34 31 1/34 1/31 65/1054 16.2

26 32 1/26 1/32 58/832 14.3

Calculations

Discussion

Precautions

Conclusion


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EXPERIMENT 16: Length of a wire and resistanceTITLE: Electricity and MagnetismAIM: Investigating the relationship between change in the length of a wire and resistanceTheory: The resistance of a wire is directly proportional to the length of a wire as shown by therelationship R L/A.with A being the crosssectional area of the wire. (R=kL/A), k = resistivityconstant


Resistance meter

Method:

1. The material to be assessed (Copper, Aluminum etc) was chosen.

2. The thickness of the material 0.25cm was selected

3. The starting length of the wire and the corresponding resistance for this length wasselected. These values were recorded in a table.

4. The length was increased by a steady value e.g. 10cm and the corresponding change ofresistance recorded in the same table.

ResultsLength (cm) Resistance ()

2.245.47.610

1.562.433.25.377.07

R=Resistivity

A

0.17 Copper per Cm


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EXPERIMENT 17: Thickness of a wire and resistanceTITLE: Electricity and MagnetismAIM: To investigate the relationship between change in the thickness of a wire and resistanceSKILL: P & DDATE:Theory: The resistance of a wire is inversely proportional to the area of a wire as shown by therelationship


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EXPERIMENT 18: Voltage characteristic of a LampTITLE: Electricity and MagnetismDATE:AIM: To Investigate the voltage characteristic of a lampTheory: The voltage in a circuit relates to the current and the resistance by the relationship V =I.R, where I = the current flowing through the lamp and R = the resistance of the lampApparatus and Mater ials:

Voltmeter

Power supply etc

Method:

1. A circuit was set up similar to the one below. The current flowing was of a givenvalue but the resistance could be varied by the variable resistor

2. The resistance was increased incrementally for about 5 different values and thecorresponding changes in voltage across the resistor in the circuit was noted.

3. These values were recorded in a suitable table

4. The relationship of V to R when I is constant was deduced.


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EXPERIMENT 19:Effect of distance (from the detector) on the transmission of beta radiationTITLE: Physics of the atomAIM: To find the effect of distance (from the detector) on the transmission of beta radiationDATE:Skill:Theory: Beta radiation is one of three types of particles emitted from radioactive sources. It is thesecond most penetrating type of radiation (after gamma) and is absorbed fairly rapidly by airmolecules but is still able to travel several cm in air from its source. In this experiment the traveldistance of these particles will be assessed.Apparatus and Mater ials:

Geiger counter

Beta radiation source etc

Method:

1. The level of background radiation was determined before placing the source in frontof the detector.

2. The counter was reset and the experiment was repeated three times to get an averagecount per second for the background radiation.

3. The results were recorded in a suitable table

4. The beta radiation source was placed 30cm from the detector. The counter was resetand used to determine the count rate for the next 10 seconds.

5. This was repeated twice or thrice for this distance and the results recorded in thetable.

6. The distance was moved to 25cm and step 5 repeated.

7. The distance was decreased by 5cm until a distance of 10cm was reached, the resultswere recorded in the table.

8. A graph was plotted showing the average count rate vs distance (x axis)

9. A reasonable discussion and conclusion were written


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Source Distance

(cm)CountDuration(sec)

Count Average

CountRate

30

25

20

15

10

10039

13876

1999

30475

49821


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EXPERIMENT 20: Effect of shielding materials on the transmission of beta radiationTITLE: Physics of the atomAIM: Effect of shielding materials on the transmission of beta radiationSKILL: P & DDATE:Theory: Materials can absorb beta radiation by varying degrees. In some cases, these materials arequite permeable and very little absorption takes place. In other cases, the materials are highlyabsorptive and very few beta particles can penetrate the material. Plan and design your experimentto show how you would assess this.

Apparatus and Materials:(YOU DETERMINE THE MATERIALS NEEDED FOR THIS EXPERIMENT)

METHOD: (YOU DETERMINE THIS)

cxc physics lab

Documents

mlaverage volume

new volume

atom effect of distance

mater ials jamaican

pendulumpd6 mechanics

latent heat of fusion

meter rule8 mechanics

focal length