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CHAPTER 1:INTRODUCTION TO PHYSICS1.1 PENDULUM

Hypothesis:The longer the length of a simple pendulum, the longer the period of oscillation.Aim of the experiment:To investigate how the period of a simple pendulum varies with its length.Variables:Manipulated: The length of the pendulum, lResponding: The period of the pendulum, TConstant: The mass of the pendulum bob, gravitational accelerationApparatus/Materials:Pendulum bob, length of thread about 100 cm long, retort stand, stopwatchSetup:Length, l

Thread

Retort standPendulumProcedure:1. The thread is tied to the pendulum bob. The other end of the thread is tied around the arm of the retort stand so that it can swing freely. The length of the pendulum, l is measured to 80 cm as per the diagram.Chapter 1: Introduction to Physics Page 1 of 522. With the thread taut and the bob at rest, the bob is lifted at a small amplitude (of not more than 10). Ensure that the pendulum swings in a single plane.3. The time for ten complete oscillations of the pendulum is measured using thestopwatch.4. Step 3 is repeated, and the average of both readings are calculated.5. The period of oscillation, T is calculated using the average reading divided by the number of oscillations, i.e. 10.6. T2 is calculated by squaring the value of T.7. Steps 1 to 6 are repeated using l = 70 cm, 60 cm, 50 cm, and 40 cm.8. A graph T2 versus l is plotted.Recording of data:Length of pendulum, l (cm)Time of oscillations, t (s)Period of oscillation, T

t1t2AverageT = t/10 (s)T2 (s2)

80

70

60

50

40

Graph of T2 vs lT2Length of pendulum, lDiscussion:The graph of T2 versus l shows a straight line passing through the origin. This means that the period of oscillation increases with the length of the pendulum, with T2 directly proportional to l.Conclusion:The longer the length of the pendulum, the longer the period of oscillation. The hypothesis is proven valid.Chapter 1: Introduction to Physics Page 2 of 52

CHAPTER 2:FORCES AND MOTION2.1 INCLINED PLANES

Hypothesis:The larger the angle of incline, the higher the velocity just before reaching the end of the runwayAim of the experiment:To study the relationship between the velocity of motion and the angle of inclinationVariables:Manipulated: Angle of inclineResponding: Velocity just before reaching the end of the runwayConstant: Length of runwayApparatus/Materials: Trolley, protractor, wooden blocks, cellophane tape, ticker- timer, ticker tape, power supply, friction-compensated runwaySetup:

Procedure:1. The apparatus is set up as per the diagram, and the inclined angle of the plane is measured using a protractor. An initial angle of 5 is used.2. The ticker-timer is started up and at the same time the trolley is released to slide downthe plane.3. The final velocity when the trolley reaches the end of the plane is calculated using the distance of 10 ticks on the ticker tape.4. The procedure is repeated by changing the angle of incline to 10, 15, 20 and 25.Chapter 2: Forces and Motion Page 3 of 52Results:Angle of incline ()Final velocity (m s-1)

5

10

15

20

25

Analysis:A graph of the velocity of the trolley against the angle of incline is plotted as follows:Velocity (m s-1)Angle of incline ()Conclusion:A higher angle of incline will have a higher velocity at the end of the runway. Hypothesis accepted.Note: The experiment can be modified by making the angle constant and varying the height and length of the runway. Changes must be made accordingly: hypothesis, variable list, procedure, table, analysis, conclusion.Chapter 2: Forces and Motion Page 4 of 522.2 INERTIA

Option 1: Using a saw bladeHypothesis:The larger the mass, the larger the inertiaAim of the experiment:To study the effect of mass on the inertia of an objectVariables: Manipulated: Mass, mResponding: Period of oscillation, TConstant: Stiffness of blade, distance of the centre of the plasticine from the clampApparatus/Materials: Jigsaw blade, G-clamp, stopwatch, and plasticine spheres of mass 20 g, 40 g, 60 g, 80 g, and 100 gSetup:Procedure:1. One end of the jigsaw blade is clamped to the leg of a table with a G-clamp as per the diagram drawn.2. A 20 g plasticine ball is fixed at the free end of the blade.3. The free end of the blade is displaced horizontally and released so that it oscillates.The time for 10 complete oscillations is measured using a stopwatch. This step is repeated. The average of 10 oscillations is calculated. Then, the period of oscillation is determined.4. Steps 2 and 3 are repeated using plasticine balls with masses 40 g, 60 g, 80 g, and 100 g.5. A graph of T2 versus mass of load, m is drawn.Chapter 2: Forces and Motion Page 5 of 52Results:Mass of load, m (g)Time of oscillations, t (s)Period of oscillation, T

t1t2AverageT = t/10 (s)T2 (s2)

20

40

60

80

100

Graph of T2 versus m:Discussion:The graph of T2 versus m shows a straight line passing through the origin. This means that the period of oscillation increases with the mass of the load; that is, an object with a large mass has a large inertia.Conclusion:Objects with a large mass have a large inertia. This is the reason why it is difficult to set an object of large mass in motion or to stop it. The hypothesis is valid.Option 2: Using an inertia balanceHypothesis:The larger the mass, the bigger the inertiaAim of the experiment:To study the effect of mass on the inertia of an objectVariables: Manipulated: Mass, mResponding: Period of oscillation, TConstant: Stiffness of the inertia balanceApparatus/Materials: Inertia balance, masses for the inertia balance, G-clamp, stopwatchChapter 2: Forces and Motion Page 6 of 52Setup:Procedure:1. The inertia balance is set up by clamping it onto one end of the table as shown in the figure above.2. One mass is placed into the inertia balance. The inertia balance is displaced to one side so that it oscillates in a horizontal plane.3. The time for 10 complete oscillations is measured using a stopwatch. This step is repeated. The average of 10 oscillations is calculated. Then, the period of oscillation is determined.4. Steps 2 and 3 are repeated using two and three masses on the inertia balance.5. A graph of T2 versus number of masses, n is drawn.Results:Number of masses, nTime of oscillations, t (s)Period of oscillation, T

t1t2AverageT = t/10 (s)T2 (s2)

1

2

3

Graph of T2 versus m:Discussion:The graph of T2 versus m shows a straight line passing through the origin. This means that the period of oscillation increases with the mass of the load; that is, an object with a large mass has a large inertia.Conclusion:Objects with a large mass have a large inertia. This is the reason why it is difficult to set an object of large mass in motion or to stop it. The hypothesis is valid.Chapter 2: Forces and Motion Page 7 of 522.3 PRINCIPLE OF CONSERVATION OF MOMENTUM

Experiment 1: Elastic collisionsHypothesis:The total momentum before collision is equal to the total momentum after collision, provided there are no external forces acting on the systemAim of the experiment:To demonstrate conservation of momentum for two trolleys colliding with each other elasticallyVariables:Manipulated: Mass of trolleysResponding: Final velocities of the trolleys / Momentum of the trolleysConstant: Surface of ramp usedApparatus/Materials: Friction-compensated runway, ticker-timer, A.C. power supply, trolleys, wooden block, ticker tape, cellophane tapeSetup:Procedure:1. The apparatus is set up as shown in the diagram.2. The runway is adjusted so that it is friction-compensated.3. Two trolleys of equal mass are selected. A spring-loaded piston is fixed to the front end of trolley A.4. Two pieces of ticker tape are attached to trolleys A and B respectively withcellophane tape. The ticker tapes are separately passed through the same ticker-timer.5. The ticker-timer is switched on and trolley A is given a slight push so that it moves down the runway at uniform velocity and collides with trolley B which is stationary.6. The ticker-timer is switched off when both trolleys reach the end of the runway.7. From the ticker tapes of trolleys A and B, the final velocities are determined.8. Momentum is calculated using the formula p = mv.9. The experiment is repeated using different masses of trolleys.Chapter 2: Forces and Motion Page 8 of 52Recording of data:mAmBBefore collisionAfter collision

uAInitial total momentum,mAuAvAvBFinal total momentum,mAvA + mBvB

mm

m2m

2 mm

2 m2 m

Analysis:From the above table, it is found that:Total momentum before collision = Total momentum after collisionConclusion: Hypothesis proven.Experiment 2: Inelastic collisionsHypothesis:The total momentum before collision is equal to the total momentum after collision, provided there are no external forces acting on the systemAim of the experiment:To demonstrate conservation of momentum for two trolleys colliding with each other inelasticallyVariables:Manipulated: Mass of trolleysResponding: Final velocities of the trolleys / Momentum of the trolleysConstant: Surface of ramp usedApparatus/Materials: Friction-compensated runway, ticker-timer, A.C. power supply, trolleys, wooden block, ticker tape, cellophane tape, plasticine / VelcroSetup:Chapter 2: Forces and Motion Page 9 of 52Procedure:1. The apparatus is set up as shown in the diagram.2. The runway is adjusted so that it is friction-compensated.3. Two trolleys of equal mass are selected. Plasticine is fixed to the front end of trolleyA. (Alternatively, use Velcro pads)4. A ticker tape is attached to trolley A with cellophane tape. The ticker tape is passed through the ticker-timer.5. The ticker-timer is switched on and trolley A is given a slight push so that it moves down the runway at uniform velocity and collides with trolley B which is stationary.6. The ticker-timer is switched off when both trolleys reach the end of the runway.7. The final velocity is determined from the ticker tape.8. Momentum is calculated using the formula p = mv.9. The experiment is repeated using different masses of trolleys.Results:mAmBBefore collisionAfter collision

uInitial total momentum,mAuAvFinal total momentum, (mA + mB) v

mm

m2m

2 mm

2 m2 m

Analysis:From the above table, it is found that:Total momentum before collision = Total momentum after collisionConclusion: Hypothesis proven.Experiment 3: ExplosionHypothesis:The total momentum before collision is equal to the total momentum after collision, provided there are no external forces acting on the systemAim of the experiment:To demonstrate conservation of momentum for two trolleys moving away from each other from an initial stationary positionVariables:Manipulated: Mass of trolleysResponding: Final velocities of the trolleys / Momentum of the trolleysConstant: Surface usedChapter 2: Forces and Motion Page 10 of 52

Apparatus/Materials: Trolleys, wooden blocks, ticker tape, cellophane tapeSetup:Before explosion After explosionProcedure:1. The apparatus is set up as shown in the diagram.2. Two trolleys A and B of equal mass are placed in contact with each other on an even and smooth surface. Two wooden blocks are placed on the same row at the end of each trolley respectively.3. The vertical trigger on trolley B is given a light tap to release the spring-loaded piston which then pushes the trolleys apart. The trolleys collide with the wooden blocks.4. The positions of the wooden blocks are adjusted so that both the trolleys collide with them at the same time.5. The distances, dA and dB are measured and recorded.6. The experiment is repeated with different masses of trolleys.Results:Before explosionAfter explosion

Initial total momentumMass of trolley A, mAMass of trolley B, mBDistance traveled by trolley A, dADistance traveled by trolley B, dBFinal total momentum, mAdA + mB(-dB)

0mm

0m2m

02 mm

02m2m

Analysis:Because both trolleys hit the wooden blocks at the same time, the velocity of the trolleys can be represented by the distance traveled by the trolleys.From the above table, it is found that:Initial total momentum = 0Final total momentum = 0 Total momentum before collision = Total momentum after collisionConclusion: Hypothesis proven.Chapter 2: Forces and Motion Page 11 of 522.4 FORCE, MASS AND ACCELERATION

Experiment 1: Relationship between acceleration and mass when force is constantHypothesis:When the force applied is constant, the acceleration of an object decreases when its mass increasesAim of the experiment:To study the effect of mass of an object on its acceleration if the applied force is constantVariables: Manipulated: Mass, m Responding: Acceleration, a Constant: Applied force, FApparatus/Materials: Ticker-timer, A.C. power supply, trolleys, elastic band, runway, wooden block, ticker tape, cellophane tapeSetup:Procedure:1. Apparatus is set up as shown in the diagram.2. A ticker-tape is attached to the trolley and passed through the ticker-timer.3. The ticker-timer is switched on and the trolley is pulled down the inclined runway with an elastic band attached to the hind post of the trolley.4. The elastic band must be stretched to a fix length that is maintained throughout the motion down the runway.5. When the trolley reaches the end of the runway, the ticker-timer is switched off andthe ticker tape is removed.6. Starting from a clearly printed dot, the ticker tape is divided into strips with each strip containing 10 ticks.7. A ticker tape chart is constructed, and from the chart, the acceleration of the trolley iscalculated.8. The experiment is repeated using 2 and 3 trolleys. The elastic band must be stretched to the same fixed length as in step 4.Chapter 2: Forces and Motion Page 12 of 52Results:Mass of trolley, m (kg)1mAcceleration, a (m s-2)

1 trolley

2 trolleys

3 trolleys

Analysis:A graph of a againsta

1 is drawn.m1mFrom the graph, it shows that a 1mConclusion:The acceleration of an object decreases when the mass increases. Hypothesis proven.Experiment 2: Relationship between acceleration and force when mass is constantHypothesis:When the mass is constant, the acceleration of an object increases when the applied force increasesAim of the experiment:To study the effect of force on an objects acceleration if its mass is constantVariables:Manipulated: Applied force, F Responding: Acceleration, a Constant: Mass, mApparatus/Materials: Ticker-timer, A.C. power supply, trolleys, elastic band, runway, wooden block, ticker tape, cellophane tapeChapter 2: Forces and Motion Page 13 of 52Setup:Procedure:1. Apparatus is set up as shown in the diagram.2. A ticker-tape is attached to the trolley and passed through the ticker-timer.3. The ticker-timer is switched on and the trolley is pulled down the inclined runway with an elastic band attached to the hind post of the trolley.4. The elastic band must be stretched to a fix length that is maintained throughout themotion down the runway.5. When the trolley reaches the end of the runway, the ticker-timer is switched off and the ticker tape is removed.6. Starting from a clearly printed dot, the ticker tape is divided into strips with each strip containing 10 ticks.7. A ticker tape chart is constructed, and from the chart, the acceleration of the trolley iscalculated.8. The experiment is repeated using 2 and 3 elastic bands. The elastic bands must be stretched to the same fixed length as in step 4.Results:Force applied, FAcceleration, a (m s-2)

1 unit

2 units

3 units

Analysis:A graph of a against F is drawn.aFFrom the graph, it shows that a FConclusion:The acceleration of an object increases when the applied force increases. Hypothesis proven.

Chapter 2: Forces and Motion Page 14 of 522.5 GRAVITATIONAL ACCELERATION

Hypothesis:Gravitational acceleration does not depend on an objects massAim of the experiment:To measure the acceleration due to gravityVariables: Manipulated: Mass, mResponding: Gravitational acceleration, gApparatus/Materials: Ticker-timer, ticker tape, A.C. power supply, retort stand, weights (50 g 250 g), G-clamp, cellophane tape, soft boardSetup:Procedure:1. Apparatus is setup as shown in the diagram above.2. One end of the ticker tape is attached to a 50 g weight with cellophane tape, and the other end is passed through the ticker timer.3. The ticker-timer is switched on and the weight is released so that it falls onto the softboard.4. The ticker-timer is switched off when the weight lands on the soft board.5. Gravitational acceleration is calculated from the middle portion of the ticker tape.6. The experiment is repeated with weights of mass 100 g, 150 g, 200 g, and 250 g.Chapter 2: Forces and Motion Page 15 of 52Results:Mass of weights (g)Free fall acceleration (m s-2)

50

100

150

200

250

Analysis:From the table above, it is found that the gravitational acceleration for all the weights of different masses are the same.Discussion: The value of the gravitational acceleration, g obtained is less than the standard valueof 9.81 m s-2 This is because the weight is not falling freely. It is affected by:o Air resistanceo Friction between ticker tape and ticker-timerConclusionGravitational acceleration is not dependent on the mass of the object. Hypothesis proven.2.6 PRINCIPLE OF CONSERVATION OF ENERGY

Hypothesis:Energy cannot be created or destroyed, it can only change form.Aim of the experiment:To investigate the conversion of gravitational potential energy to kinetic energy.Variables: Manipulated: Mass, m Responding: Final velocity, v Constant: Height, hApparatus/Materials: Ticker-timer, ticker tape, A.C. power supply, trolley, thread, weights, smooth pulley, friction-compensated runway, soft board, cellophane tapeChapter 2: Forces and Motion Page 16 of 52

Setup:Procedure:1. Apparatus is setup as shown in the diagram above.2. One end of the ticker tape is attached to the back of the trolley with cellophane tape and the other end is passed through the ticker-timer.3. The ticker-timer is switched on, and the trolley is released.4. The final velocity of the trolley and the weight is determined from the ticker tape obtained.

5. The experiment is repeated with different masses of trolleys and weights.Results:Mass of trolley = M kgMass of weight = m kgHeight of weight before release = h mFinal velocity of trolley and weight = v m s-1Loss of potential energy of the weight = mghFinal kinetic energy of the trolley and the weight = (M + m) v2It is found that (M + m) v2 = mghConclusionThe loss of potential energy is converted to kinetic energy. Hypothesis proven.Note: The experiment can be modified by making the mass constant and changing the height of the weights release. Changes must be made to the variables list and to the last step of the procedure.Chapter 2: Forces and Motion Page 17 of 522.7 HOOKES LAW

Hypothesis:The bigger the weight, the longer the spring extensionAim of the experiment:To determine the relationship between the weight and the spring extensionVariables:Manipulated: Weight of the load Responding: Spring extension Constant: Spring constantApparatus and Materials: Spring, pin, weights, plasticine, retort stand, metre ruleSetup:Procedure:1. The apparatus is setup as shown in the diagram.2. The length of the spring without any weights, l0 is measured using the metre rule with the pin as reference.3. A 50 g weight is hung from the bottom of the spring. The new length of the spring, lis measured. The spring extension is l l0.4. Step 4 is repeated with weights 100 g, 150 g, 200 g, and 250 g.Chapter 2: Forces and Motion Page 18 of 52Results:Original length of spring = l0 = cmLoad mass(g)Load weight(N)Spring length, l(cm)Spring extension, x = l l0(cm)

50 g0.5 N

100 g1.0 N

150 g1.5 N

200 g2.0 N

250 g2.5 N

Analysis:A graph of spring extension, x against weight, F is plotted.xFThe x-F graph is a linear graph which passes through the origin. This shows that the extension of the spring is directly proportional to the stretching force.Conclusion: Hypothesis proven.Chapter 2: Forces and Motion Page 19 of 52

CHAPTER 3:FORCES AND PRESSURE3.1 PRESSURE IN LIQUIDS

Experiment 1: Water pressure and depthHypothesis:Water pressure increases with depthAim of the experiment:To find the relationship between the pressure in a liquid according to its depthVariables:Manipulated: Depth of liquid Responding: Pressure in liquid Constant: Density of liquidApparatus and Materials: Measuring cylinder, thistle funnel, rubber tube, manometer, metre ruleSetup:Procedure:1. Apparatus is set up as shown in the diagram.2. The measuring cylinder is completely filled with water.3. The thistle funnel is lowered into the water to a depth of 10.0 cm. The manometer reading is measured. The difference in the liquid heights in the manometer represent the pressure reading.4. Step 3 is repeated with values of depth 20.0 cm, 30.0 cm, 40.0 cm and 50.0 cm.Chapter 3: Forces and Pressure Page 20 of 52Results:Depth (cm)Manometer reading (cm)

10.0

20.0

30.0

40.0

50.0

Analysis:A graph of pressure against depth is drawn. Pressure

DepthConclusion:It is observed that the manometer reading increases as the depth of the thistle funnel increases. This shows that the pressure increases with the depth of the liquid. Hypothesis proven.Experiment 2: Water pressure and densityHypothesis:Pressure in liquid increases with its densityAim of the experiment:To find the relationship between the pressure in a liquid and its densityVariables:Manipulated: Density of liquid Responding: Pressure in liquid Constant: Depth of liquidApparatus and Materials: Measuring cylinder, thistle funnel, rubber tube, manometer, metre rule, water, glycerin, alcoholChapter 3: Forces and Pressure Page 21 of 52Setup:Procedure:1. Apparatus is set up as shown in the diagram.2. The measuring cylinder is completely filled with water.3. The thistle funnel is lowered into the water to a depth of 50.0 cm. The manometer reading is measured. The difference in the liquid heights in the manometer represent the pressure reading.4. The experiment is repeated by replacing the water with glycerin (density = 1300 kg m-3) and alcohol (density = 800 kg m-3).Results:Depth within liquid = 50.0 cmLiquidDensity (kg m-3)Manometer reading (cm)

Water1000

Glycerin1300

Alcohol800

Conclusion:It is observed that the manometer reading increases as the density of the liquid increases. This shows that the pressure increases with the density of the liquid.Hypothesis proven.Chapter 3: Forces and Pressure Page 22 of 523.2 ARCHIMEDES PRINCIPLE

Hypothesis:The buoyant force on an object in a liquid is equal to the weight of the liquid displacedAim of the experiment:To find the relationship between the buoyant force acting upon an object in a liquid and the weight of the liquid displacedVariables:Manipulated: Weight of the objectResponding: Buoyant force / Weight of liquid displacedConstant: Density of liquid usedApparatus and Materials: Eureka tin, spring balance, stone, thread, beaker, triple beam balanceSetup:Procedure:1. A beaker is weighed with the triple beam balance and its mass, m1 is recorded.2. The Eureka tin is filled with water right up to the level of the overflow hole. Thebeaker is placed beneath the spout to catch any water that flows out.3. A stone is suspended from the spring balance with thread and its weight in air, W1 is read from the spring balance.Chapter 3: Forces and Pressure Page 23 of 52

4. The stone is lowered into the Eureka tin until it is completely immersed in water without touching the bottom of the Eureka tin. The water will overflow into the beaker.

5. The spring balance reading, W2 is recorded.6. The beaker with water is weighed with the triple beam balance, and the mass, m2 isrecorded.Results:Weight of stone in air = W1Weight of stone in water = W2Buoyant force acting on the stone = W2 W1Weight of the empty beaker = m1gWeight of the beaker and displaced water = m2gWeight of the displaced water = (m2 m1)gIt is found that W2 W1 = (m2 m1)gDiscussion:The loss of weight of the stone immersed in water is due to the buoyant force of the water acting upon it.From the results, it is found that the loss in weight of the stone is equal to the weight ofwater displaced.Conclusion:Buoyant force on the stone = Weight of the water displaced by the stoneHypothesis proven.Note: Experiment can be modified to compare the weight of different sized stones and the values of buoyant force3.3 PASCALS PRINCIPLE

Hypothesis:The liquid pressure exerted on a small surface is equal to the liquid pressure exerted on a large surface in a closed systemAim of the experiment:To find the relationship between the pressure in a small syringe and a large syringe in a closed systemVariables:Manipulated: Pressure acting on the small syringe Responding: Pressure acting on the large syringe Constant: Density of liquid within the systemChapter 3: Forces and Pressure Page 24 of 52Apparatus and Materials: 5 ml syringe, 10 ml syringe, several weights, rubber tube, two retort standsSetup:Procedure:1. The diameters of the piston of both syringes are measured and their cross-sectional areas are calculated.2. The two syringes are each mounted on a retort stand.3. The syringes are filled with water and are securely connected to each other with a rubber tube as shown in the diagram.4. A weight is placed on the piston of the small syringe.5. Weights are added to the piston of the large syringe until the water levels in the two syringes are the same (i.e. syringes are in equilibrium).6. The forces, F1 and F2 on the syringes are calculated.7. The pressure, P1 and P2 exerted on the syringes are compared.Results:Syringe sizeCross-sectional area, AMass of the weight, mForce exerted on the syringe, F = mgPressure, P= F A

SmallA1m1F1P1

LargeA2m2F2P2

Discussion:It is found that the pressure, P1 exerted on the piston of the small syringe is equal to the pressure, P2 exerted on the piston of the large syringe.Conclusion:The water pressure exerted on the piston of the small syringe is equal to the waterpressure exerted on the piston of the large syringe. This shows that the pressure applied to the piston of the small syringe is transmitted to the piston of the large syringe.Hypothesis proven.Chapter 3: Forces and Pressure Page 25 of 523.4 BERNOULLIS PRINCIPLE

Hypothesis:When the velocity of water increases, its pressure decreases and vice versa.Aim of the experiment:To find the effects of movement on the pressure exerted by a fluidVariables:Manipulated: Velocity of the water Responding: Pressure of the water Constant: Density of the waterApparatus and Materials: Uniform glass tube, Venturi tube, rubber hose, water from a tapProcedure:1. A uniform glass tube is connected to a tap with a rubber hose. The other end of the tube is closed up with a stopper.2. The tap is opened slowly so that water flows into it.3. The levels of the vertical tubes are observed.4. The stopper is then removed. The tap is adjusted so that the water flows through the tube at a uniform rate.5. The levels of the vertical tubes are observed.6. The experiment is repeated by replacing the uniform glass tube with a Venturi tube.Results:Uniform glass tube:

With the stopper Without the stopperChapter 3: Forces and Pressure Page 26 of 52Venturi tube:

With the stopper Without the stopperDiscussion: The height of the water in the vertical tube represents the pressure at that point. When water is not flowing, the pressure along the entire tube is the same, thereforethe water levels in all three vertical tubes are the same. For the uniform glass tube:o Water flows from high pressure to low pressure.o Therefore, the water levels are decreasing because the pressure is decreasing. For the Venturi tube:o The velocity at Y is higher because of the smaller cross-sectional area.o Therefore, the pressure at Y is the lowest.o Pressure still decreases from X to Z because water flows from high pressure tolow pressure.Conclusion:The higher the water velocity, the lower the pressure at that point. Hypothesis proven.Chapter 3: Forces and Pressure Page 27 of 52

CHAPTER 4:HEAT AND ENERGY4.1 SPECIFIC HEAT CAPACITY

Experiment 1: Rise in temperature varying mass, fixed amount of heatHypothesis:The bigger the mass of water, the smaller the rise in temperature when supplied with the same amount of heatAim of the experiment:To determine the rise in temperature of water with varying massesVariables:Manipulated: Mass of water, m Responding: Rise in temperature, Constant: Amount of heat supplied, QApparatus and Materials: Beaker, electric heater, thermometer, stopwatch, triple beam balance, stirrer, polystyrene sheet, felt clothSet up:Procedure:1. With the help of a triple beam balance, fill a beaker with water of mass 0.40 kg.2. The apparatus is set up as shown in the diagram.3. The initial temperature of the water, 1 is measured using a thermometer and is recorded.

4. The electric heater is placed into the water and is switched on for 1 minute. The water is continuously stirred.5. The water is continuously stirred even after the heater has been switched off. TheChapter 4: Heat and Energy Page 28 of 526. The highest temperature the water reaches, 2 is measured and recorded. The rise in temperature, = 2 1 is calculated.7. The experiment is repeated with water of mass 0.50 kg, 0.60 kg, 0.70 kg, and 0.80 kg.8. A graph of against m and a graph of againstResults:

1 are plotted.mMass of water,m (kg)Initial temperature, 1 (C)Final temperature, 2 (C)Rise in temperature, = 2 1 (C)1 (kg-1)m

0.40

0.50

0.60

0.70

0.80

Analysis: The amount of heat supplied is made constant by using the same heater for the sameperiod of time. The following graphs are obtained:Conclusion:The rise in temperature is inversely proportional to the mass when a constant amount of heat is supplied. Hypothesis proven.Experiment 2: Rise in temperature fixed mass, varying amount of heatHypothesis:When more heat is supplied to water of fixed mass, the rise in temperature is greaterAim of the experiment:To determine the rise in temperature of water with varying amounts of heatVariables:Manipulated: Amount of heat supplied, Q Responding: Rise in temperature, Constant: Mass of water, mChapter 4: Heat and Energy Page 29 of 52Apparatus and Materials: Beaker, electric heater, thermometer, stopwatch, triple beam balance, stirrer, polystyrene sheet, felt clothSet up:Procedure:1. With the help of a triple beam balance, fill a beaker with water of mass 0.50 kg.2. The apparatus is set up as shown in the diagram.3. The initial temperature of the water, 1 is measured using a thermometer and is recorded.

4. The electric heater is placed into the water and is switched on for 1 minute. The water is continuously stirred.5. The water is continuously stirred even after the heater has been switched off.6. The highest temperature the water reaches, 2 is measured and recorded. The rise in temperature, = 2 1 is calculated.7. The experiment is repeated with water of the same mass but with heating time of 2 minutes, 3 minutes, and 4 minutes.8. A graph of against t is plotted.Results:Heating time(minute)Initial temperature, 1 (C)Final temperature, 2 (C)Rise in temperature, = 2 1 (C)

1

2

3

4

Analysis: Because the same heater with fixed power is used, the heating time, t is definedoperationally as the heat quantity. The following graph is obtained:Chapter 4: Heat and Energy Page 30 of 52

Conclusion:When an object of fixed mass is heated, the rise in temperature changes proportionally to the amount of heat supplied. Hypothesis proven.Experiment 3: Determining the specific heat capacity of aluminiumAim of the experiment:To determine the specific heat capacity of aluminiumApparatus and Materials: Aluminium cylinder, weighing scale, electric heater, thermometer, power supply, felt cloth, polystyrene sheet, stopwatch, lubricating oilSet up:Procedure:1. An aluminium cylinder with two cavities is weighed and its mass, m is recorded.2. The electrical power of the heater, P is recorded.3. The electrical heater is then placed inside the large cavity in the centre of the cylinder.4. The thermometer is then placed in the small cavity of the aluminium cylinder.5. A few drops of lubricating oil are added to both cavities to ensure good thermal contact (better heat transfer).6. The apparatus is set up as shown in the diagram above.7. The initial temperature of the aluminium cylinder, 1 is recorded.8. The electric heater is switched on and the stopwatch is started simultaneously.9. After heating for t seconds, the heater is switched off. The highest reading on the thermometer, 2 is recorded.10. The experiment is repeated and an average value of c is calculated.Chapter 4: Heat and Energy Page 31 of 52Results:Electric power of heater = P WattHeating time = t secondsMass of aluminium cylinder = m kgInitial temperature of the aluminium cylinder = 1Final temperature of the aluminium cylinder = 2Temperature rise = 2 1Electrical energy supplied by the heater = PtHeat energy absorbed by the aluminium cylinder = mcOn the assumption that there is no heat loss to the surroundings: Heat supplied = Heat absorbedPt = mcSpecific heat capacity, c = Pt mDiscussion: The aluminium cylinder is wrapped with a felt cloth to reduce the heat loss to thesurroundings and the polystyrene sheet acts as a heat insulator to avoid heat loss to the surface of the table. The value of the specific heat capacity of aluminium, c determined in the experimentis larger than the standard value. This is because there will be some heat lost to the surrounding. The temperature of the aluminium cylinder will continue to rise after the electricalheater has been switched off because there is still some heat transfer from the heater to the cylinder.Conclusion:The specific heat capacity of aluminium is a constant.4.2 SPECIFIC LATENT HEAT

Experiment 1: Heating of naphthaleneHypothesis:During the change of state of naphthalene from solid to liquid, there is no change in temperature when heat is continuously suppliedAim of the experiment:To observe the change in temperature when naphthalene is meltingApparatus and Materials: Boiling tube, naphthalene powder, beaker, thermometer, Bunsen burner, stopwatch, retort stand, tripod stand, wire gauzeChapter 4: Heat and Energy Page 32 of 52Set up:Procedure:1. The apparatus is set up as shown in the diagram.2. The initial temperature of the naphthalene is recorded.3. The Bunsen burner is lighted and the stopwatch started.4. The temperature of the naphthalene is recorded at 1 minute intervals until the temperature reaches 100C.5. The state of the naphthalene is observed and tabulated throughout the heating process.6. A graph of temperature against time is drawn.Results:Time, t (minute)Temperature of naphthalene, (C)

0

1

2

3

Graph of temperature against time:Discussion: The temperature-time graph shows that the temperature of naphthalene rises until thenaphthalene starts to melt. The naphthalene starts to melt at 80C. The temperature remains constant at this valuefor several minutes while the naphthalene continues to melt with the heat.Chapter 4: Heat and Energy Page 33 of 52 After the naphthalene has completely melted, the temperature begins to rise withcontinued heating.Conclusion:The temperature of the naphthalene remains constant during a change of state from solid to liquid.Experiment 2: Cooling of naphthaleneHypothesis:During the change of state of naphthalene from liquid to solid, there is no change in temperatureAim of the experiment:To observe the change in temperature when naphthalene is freezingApparatus and Materials: Boiling tube, naphthalene powder, beaker, thermometer, Bunsen burner, stopwatch, retort stand, tripod stand, wire gauzeSet up:Procedure:1. The apparatus is set up as shown in the diagram.2. The naphthalene is heated until the temperature reaches 95C.3. The boiling tube is then removed from the water bath and the outer part of the tube is dried.

4. The temperature of the naphthalene is recorded every minute until the temperaturedrops to about 60C.5. A graph of temperature against time is drawn.Chapter 4: Heat and Energy Page 34 of 52Results:Time, t (minute)Temperature of naphthalene, (C)

0

1

2

3

Graph of temperature against time:

Discussion: The temperature-time graph shows that the temperature of naphthalene drops until80C where it stays constant for several minutes as it freezes. After the naphthalene has completely frozen, the temperature continues to drop.Conclusion:The temperature of the naphthalene remains constant during a change of state from liquid to solid.Experiment 3: Latent heat of fusion (ice)Aim of the experiment:To determine the latent heat of fusion of iceApparatus and Materials: Pure ice, electric immersion heater, filter funnel, beaker, stopwatch, weighing balance, power supply, retort stand, clampChapter 4: Heat and Energy Page 35 of 52Set up:Set A Set BProcedure:1. The mass of two empty beakers, A and B are determined using the weighing balance.2. The apparatus is arranged as shown in the diagram above.3. Each of the two filter funnels is filled with ice cubes.4. The immersion heater in Set A, the control experiment, is not connected to the power supply. The purpose of Set A is to determine the mass of the ice melted by the surrounding heat. The heater in Set B is switched on.5. When water starts to drip from the filter funnels at a steady rate, the stopwatch is started and the empty beakers A and B are placed beneath the filter funnels.6. After a period of t seconds, the heater B is switched off. The masses of both beakers,A and B are determined using the weighing balance.7. The experiment is repeated to get an average value.Results: Set A:Mass of empty beaker = mA1 kgMass of beaker + water = mA2 kgMass of ice melted by surrounding heat, ma = mA2 mA1 kgSet B:Mass of empty beaker = mB1 kgMass of beaker + water = mB2 kgMass of ice melted by surrounding heat & immersion heater, mb = mB2 mB1 kgMass of ice melted by the electric immersion heater, m = mb ma kg Electrical energy supplied by the electrical immersion heater, E = Pt Heat energy absorbed by the ice during melting, Q = mLAssuming there is no heat loss to the surroundings:Electrical energy supplied = Heat energy absorbed by the melting icePt = mLSpecific latent heat of fusion of ice, L = Pt mChapter 4: Heat and Energy Page 36 of 52Discussion: The purpose of Set A, the control experiment, is to determine the mass of ice meltedby the surrounding heat. The immersion heater must be fully immersed in the ice cubes to avoid or reduce heatloss. The stopwatch is not started simultaneously when the immersion heater is switchedon because the immersion heater requires a time period before reaching a steady temperature. At this point, the rate of melting of ice will be steady. The value of the specific latent heat of fusion of ice, L obtained in this experiment ishigher than the standard value because part of the heat supplied by the heater is lost to the surroundings.Conclusion:The specific latent heat of fusion of ice is a constant.Experiment 4: Latent heat of vapourisation (water)Aim of the experiment:To determine the latent heat of vapourisation of waterApparatus and Materials: Pure water, electric immersion heater, filter funnel, beaker, stopwatch, weighing balance, power supply, retort stand, clampSet up:Procedure:1. The apparatus is set up as shown in the diagram above.2. A beaker is placed on the platform of the electronic weighing balance.3. The electric heater is fully immersed in the water and held in this position by being clamped to a retort stand.4. The electric heater is switched on to heat the water to its boiling point.5. When the water starts to boil at a steady rate, the stopwatch is started and the reading on the electronic balance, m1 is recorded.6. The water is allowed to boil for a period of t seconds.7. At the end of the period of t seconds, the reading on the electronic balance, m2 is recorded.

Chapter 4: Heat and Energy Page 37 of 52Results:Electrical power of heater = P WattTime period of boiling = t secondsElectrical energy supplied by the electrical immersion heater, E = PtMass of water vapourised = m2 m1Heat energy absorbed by the water during vapourisation, Q = mLAssuming there is no heat loss to the surroundings:Electrical energy supplied= Heat energy absorbed by the vapourized waterPt = mLSpecific latent heat of vapourization of water, L = Pt mDiscussion: The immersion heater must be fully immersed in the water to avoid or reduce heatloss. The stopwatch is not started simultaneously when the immersion heater is switchedon because the immersion heater requires a time period before reaching a steady temperature. At this point, the rate of heating of water will be steady. The value of the specific latent heat of vapourization of water, L obtained in thisexperiment is higher than the standard value because part of the heat supplied by the heater is lost to the surroundings.Conclusion:The specific latent heat of vapourization of water is a constant.4.3 BOYLES LAW

Option 1: Changing the volume of air to measure pressureHypothesis:When the volume of air decreases, the pressure increases when its mass and temperature is constantAim:To investigate the relationship between the pressure and volume of airVariables:Manipulated: Volume of air within syringeResponding: Pressure of airConstant: Mass, temperature of airApparatus and Materials: Rubber hose, Bordon gauge, 100 cm3 syringeChapter 4: Heat and Energy Page 38 of 52Set up:

Procedure:1. Apparatus is set up as per the diagram.2. The nose of the syringe is fitted with a rubber hose and the piston is adjusted so that air volume of 100 cm3 at atmospheric pressure is trapped in the syringe.3. The rubber hose is connected to a Bourdon gauge and air pressure is read from thegauge.4. The piston of the syringe is pushed in until the trapped air volume becomes 90 cm3and the air pressure is read from the Bourdon gauge.5. Step 4 is repeated for air volume values 80, 70, and 60 cm3.Results:Volume, V (cm3)1 (cm-3)VPressure, P (Pa)

100

90

80

70

60

Analysis: A graph of P against

1 is plotted.V A linear graph going through the origin is obtained. This indicates that pressure is inversely proportional tothe volume of gas.Conclusion:Gas pressure of fixed mass is inversely proportional to its volume.

Chapter 4: Heat and Energy Page 39 of 52Option 2: Changing the pressure of air to measure volumeHypothesis:When the pressure of air decreases, the volume increases when its mass and temperature is constantAim:To investigate the relationship between the pressure and volume of airVariables:Manipulated: Pressure of airResponding: Volume of air trapped in the capillary tubeConstant: Mass, temperature of airApparatus and Materials: Bicycle pump, ruler, tank with oil, pressure gauge, glass tubeSet up:

Procedure:1. The apparatus is set up as shown in the diagram above.2. The piston of the bicycle pump is pushed in to compress the air inside the glass tube until the pressure is 10 kPa.3. When the reading on the pressure gauge is P, the volume of the air column, V is recorded.

4. Steps 1 and 2 are repeated for 5 pressure readings of 20 kPa, 30 kPa and 40 kPa.Chapter 4: Heat and Energy Page 40 of 52Results:Pressure, P (kPa)1 (Pa-1)PVolume, V (cm3)

10

20

30

40

Analysis: A graph of V against

1 is plotted.P A linear graph going through the origin is obtained. This indicates that pressure is inversely proportional to thevolume of gas.Conclusion:Volume of gas of fixed mass is inversely proportional to its pressure.4.4 CHARLES LAW

Hypothesis:When the temperature of air increases, the volume increases if the mass and pressure is constantAim:To investigate the relationship between the volume and the temperature of gasVariables:Manipulated: Air temperatureResponding: Air volumeConstant: Mass and pressure of the trapped airApparatus and Materials: Capillary tube, tall beaker, thermometer, Bunsen burner, tripod, wire gauze, retort stand, mercury or concentrated sulphuric acid, stirrer, ruler, ice, rubber bandChapter 4: Heat and Energy Page 41 of 52Set up:

Procedure:1. Apparatus is set up as per the diagram.2. The air to be studied is trapped in a capillary tube by concentrated sulphuric acid.3. The capillary tube is fitted to a ruler using two rubber bands and the bottom end of the air column is ensured to match the zero marking on the ruler.4. Water and ice is poured into the beaker until the whole air column is submerged.Water is then stirred until the temperature rises to 10 C. The length of the air column and the temperature of the water are recorded.5. Water is heated slowly while being stirred continuously. The length of the air columnis recorded every 10 C until the water temperature reaches 90 C.Results:Temperature, (C)102030405060708090

Length of air column, x (cm)

Analysis: A graph of x against is plotted. A linear graph is obtained. When extrapolated, length x = 0 occurs when gas temperature, = -273 C When the Celsius scale is replaced with the Kelvin scale, a linear graph that goes through origin is obtained.

Chapter 4: Heat and Energy Page 42 of 52Discussion:From the graph plotted, it is found that the length of the air column, x is directly proportional to its temperature, T (K). Because gas volume is directly proportional to the length of the column, it also indicates that gas volume is directly proportional to its absolute temperature.Conclusion:Gas volume of fixed mass is directly proportional to its absolute temperature4.5 PRESSURE LAW

Hypothesis:When the temperature of air increases, the pressure increases if the mass and volume is constantAim:To investigate the relationship between the pressure and the temperature of gasVariables:Manipulated: Air temperatureResponding: Air pressureConstant: Mass and volume of the trapped airApparatus and Materials: Round-bottomed flask, mercury thermometer, Bourdon gauge, Bunsen burner, tripod, wire gauze, retort stand, stirrer, iceSet up:

Chapter 4: Heat and Energy Page 43 of 52Procedure:1. Apparatus is set up as per the diagram.2. The round-bottomed flask is submerged in water and the water bath with ice is stirred continuously until the temperature of the water bath is stable.3. The temperature of the water is taken from the thermometer.4. The reading from the Bourdon gauge is read at temperatures 30, 40, 50, 60, 70 and 80C.Results:Temperature, (C)304050607080

Air pressure, P (Pa)

Analysis: A graph of P against is plotted. A linear graph is obtained. When extrapolated, pressure P = 0 occurs when gas temperature, = -273 C When the Celsius scale is replaced with the Kelvin scale, a linear graph that goes through origin is obtained.Conclusion:Gas pressure of fixed mass is directly proportional to its absolute temperatureChapter 4: Heat and Energy Page 44 of 52

CHAPTER 5:LIGHT AND VISION5.1 REFLECTION

Hypothesis:The angle of reflection is equal to the angle of incidenceAim of the experiment:To study the relationship between the angle of incidence and angle of reflectionVariables:Manipulated: Angle of incidence, i Responding: Angle of reflection, r Constant: Plane mirror usedApparatus/Materials: Light box, plane mirror, plasticine, paper, pencil, protractorSetup:Procedure:9. A straight line, PQ is drawn on a sheet of white paper.10. The normal line, ON is drawn from a point at the centre of PQ.11. With the aid of a protractor, lines at angles of incidence 15, 30, 45, 60 and 75 to the normal line, are drawn to its left.12. A plane mirror is erected along the line PQ. It is secured in this position with the aid of plasticine.13. A ray of light from the ray box is directed along the 15 line. Two positions are marked with a pencil on the line of the reflected ray.14. Step 5 is repeated for the other angles of incidence.15. The plane mirror is removed. The reflected rays are drawn by joining the respective marks.

16. The angles of reflection corresponding with all the angle of incidence are measured.The results are tabulated.Chapter 5: Light and Vision Page 45 of 52Results:Incident angle ()Reflected angle ()

15

30

45

60

75

Conclusion:The angle of incidence is equal to the angle of reflection.5.2 CURVED MIRRORS

Aim of the experiment:To study the characteristics of images formed by curved mirrorsApparatus/Materials: Concave mirror, convex mirror, plasticine, light bulb mounted on a wooden block, metre rule, white screenSetup:Procedure:1. The apparatus is set up as shown in the diagram.2. The focal length, f and the radius of curvature, r of the concave mirror, as supplied, are recorded.3. The light bulb is positioned at a distance greater than the radius of curvature of themirror, i.e. u > 2f. The white screen is moved between the concave mirror and the light bulb until an image is clearly focused on the screen. The image distance, v is measured by a metre rule and recorded.4. Step 3 is repeated with the light bulb positioned at C (u = 2f), between C and F (f < u< 2f), at F (u = f), and between F and P (u < f).Chapter 5: Light and Vision Page 46 of 525. The values of u, v, and the characteristics of the images formed are recorded in a table.

6. The experiment is repeated by replacing the concave mirror with a convex mirror.Results:Concave mirror;Position of objectObject distance, u (cm)Image distance, v (cm)Characteristics of image

Real / VirtualUpright / InvertedDiminished / Magnified / Same size

Beyond C(u > 2f)

At C(u = 2f)

Between Cand F(f < u < 2f)

At F(u = f)

Between Fand P(u < 2f)

Convex mirrors:For all positions, the image characteristics are:

Conclusion: For concave mirrors, images formed can be real or virtual, whereas for convexmirrors, only virtual images are formed. The characteristics of images formed by the concave mirror depend on the position ofthe object.5.3 REFRACTION

Hypothesis:The refracted light ray obeys Snells Law which states that the value of constant where i is the angle of incidence and r is the angle of refraction

sin isin r

is aAim of the experiment:To study the relationship between the angle of incidence and angle of refractionChapter 5: Light and Vision Page 47 of 52Variables:Manipulated: Angle of incidence, i Responding: Angle of refraction, r Constant: Plane mirror usedApparatus/Materials: Ray box, glass block, paper, pencilSetup:Procedure:1. The outline of the glass block is traced on a sheet of white paper and labeled.2. The glass block is removed. Point O is marked on one side of the glass block. With a protractor, lines forming angles of incidence 20, 30, 40, 50 and 60 are drawn and marked.

3. The glass block is replaced on its outline on the paper.4. A ray of light from the ray box is directed along 20 line. The ray emerging on the other side of the block is drawn.5. Step 4 is repeated for the other angles of incidence.6. The glass slab is removed. The points of incidence and the corresponding points of emergence are joined. The respective angles of refraction are measured with a protractor.7. The values of sin i, sin r, and

sin isin r

are calculated.Results:Angle of incidence, i ()Angle of refraction, r ()Sin iSin rn = sin isin r

20

30

40

50

60

Conclusion:It is found that

sin isin r

is a constant. Hypothesis valid.Chapter 5: Light and Vision Page 48 of 525.4 ACTUAL DEPTH & APPARENT DEPTH

Hypothesis:The deeper the actual depth, the deeper the apparent depthAim of the experiment:To study the relationship between the actual depth and apparent depthVariables:Manipulated: Actual depth, DResponding: Apparent depth, dConstant: Refractive index of medium (water), nApparatus/Materials: Tall beaker, 2 pins, ruler, metre rule, retort standSetup:

Procedure:1. Apparatus is set up as shown in the diagram.2. A pin is mounted on a movable clamp on a retort stand.3. Another pin is placed at the base of the tall beaker. Water is filled as the actual depth to D = 7.0 cm.4. The object pin O is observed from the top, and pin I is adjusted vertically until it appears to meet pin O. At this point, the position of pin I matches the apparent depth, d of pin O. The apparent depth is measured from the top of the water level to the position of pin I.5. Step 4 is repeated by changing the actual depth to 9.0 cm, 11.0 cm, 13.0 cm and 15.0 cm.

6. The results are tabulated and a graph of D against d is plotted.Chapter 5: Light and Vision Page 49 of 52Results:Actual depth, D (cm)Apparent depth, d (cm)

7.0

9.0

11.0

13.0

15.0

Analysis:A linear graph that goes through origin is obtained.DdDiscussion: The gradient of the graph is equal to the index of refraction of water.Conclusion: Hypothesis is valid5.5 TOTAL INTERNAL REFLECTION

Aim of the experiment:To determine the critical angle of glassApparatus/Materials: Semicircular glass block, ray box, protractor, white paper, pencilSetup:Procedure:1. A semicircular glass block is placed on a sheet of white paper. The outline of the glass block is traced onto the paper with a sharp pencil.Chapter 5: Light and Vision Page 50 of 522. The glass block is put aside. A normal line, NN is drawn through the centre point, Oon the diameter.3. The glass block is replaced on its outline.4. A narrow beam of light from the ray box is directed at point O at a small angle of incidence. The refracted and reflected rays are observed.5. The angle of incidence, i measured from the normal line is adjusted until the light rayis refracted along the length of the air-glass boundary. The point of entry of the light ray is marked and measured with a protractor. At this point, the incident angle is known as the critical angle, c.6. The angle of incidence is increased and the resultant rays are observed.7. The experiment is repeated by pointing the light ray through the other side of the semicircle.

Results: When i < c, part of the light ray is refracted to the air, and part of it will be reflectedback within the glass block When i = c, the light ray will be refracted along the length of the glass-air boundary When i > c, no refraction occurs; all the light ray will be totally internally reflectedwithin the glass blockAnalysis:The critical angle, c is a constant.Refractive index of glass, n =

1sin cConclusion:The refractive index of glass, n =

1 sin c5.6 LENSES

Hypothesis:The image produced by a convex lens is virtual or real depending on the position of the object. The characteristics of an image produced by a concave lens is not affected by the object distance.Variables:Manipulated: Object distance, u Responding: Image distance, v Constant: Focal length of lens, fApparatus/Materials: Cardboard with a cross-wire in triangular cut-out, light bulb, lens holder, convex lens, concave lens, white screenChapter 5: Light and Vision Page 51 of 52Setup:Procedure:1. The apparatus is set up as shown in the diagram.2. The focal length, f of the convex lens supplied is recorded.3. The object (triangle with a cross-wire) is placed at a distance greater than 2f from the convex lens.4. The white screen is moved back and forth until a sharp image of the triangle is formed on the screen. The image distance, v is measured. The characteristics of the image are observed and recorded in a table.5. Step 3 is repeated wit the object distances, u = 2f, f < u < 2f, u = f, and u < f.6. For positions where the image cannot be formed on the screen, the screen is removed and the image is viewed through the lens from the other side of the lens.7. The experiment is repeated by replacing the convex lens with a concave lens.Results: Convex lens:Position of objectObject distance, u (cm)Image distance, v (cm)Characteristics of image

Real / VirtualUpright / InvertedDiminished / Magnified / Same size

u > 2f

u = 2f

f < u < 2f

u = f

u < 2f

Concave lens:For all positions, the image characteristics are:

Conclusion: For convex lenses, images formed can be real or virtual, whereas for concave lenses,only virtual images are formed. The characteristics of images formed by the convex lens depend on the position of theobject.Chapter 5: Light and Vision Page 52 of 52