BENGKEL SCORE A+PHYSICS PAPER 2

SPM 2016

Diagram 1 shows a thermometer is used to measure the temperature of hot water.

(i) Name one type of liquid used in the thermometer.

………………………………………[1 mark]

(ii) Give one reason for the answer in 1(a)(i).

…………………………………………[1 mark]

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Mercury / alcohol

expand uniformly / does not stick to glass / opaque / high boiling point

(i) Complete the following sentence by ticking (√) the correct answer.The temperature of water is taken

when the liquid in the thermometer

…….. starts to expand.

…….. stops expanding [1 mark]

(ii) Name the physics principle involved in 1(b)(i). ……………………………………………….

[1 mark]

X

Thermal equilibrium

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Diagram 2 shows an instrument which is used to measure atmospheric pressure.

(a) Based on Diagram 2,(i) Name the instrument which is used to measure the atmospheric pressure.

………………………………………………………….

(ii) State one reason why mercury is used in the instrument.

……………………………………………………………

Barometer

Higher density // opaque // non stick

(b) Based on Diagram 2,(i) State the atmospheric pressure in the unit of cm Hg.

………………………………………………

Calculate the atmospheric pressure in the unit of Pascal.[Density of mercury = 13.6 x 103

kg m-3]

76 cm Hg

P = ƿgh= 13600 x 10 x 0.76= 1.034 x 105 Pa

Diagram 3.2 shows the electromagnetic spectrum.

(a) State the electromagnetic wave R.

..........................................................................

[1 mark]

Give one reason why microwave is used in satelite communication.

..........................................................................

[1 mark]

Gamma ray

Higer frequency / higher energy, shorter λ

A radio station emits radio wave at a

frequency of 100 MHz.

(i) State the frequency in the unit of Hz.

(ii) Calculate the wave length of the radio

wave.[speed of radio wave is 3 x 108 m s-1]

[2 marks]

100 x 106 = 1 x 108

v = fλλ = 3 x 108 / 1 x 108

= 3 m

• Diagram 4 shows ice cubes are being heated by 600 W immersion heater for 60 seconds. The melting ice cubes are collected in a beaker. The specific latent heat of fusion is 3.3 x 105 Jkg-1

(a) What is the meaning of specific latent heat of fusion?

The amount of heat required to melt 1 kg of solid without any change of temperature

(b) Explain why the temperature does not change when the ice cubes changes to liquid.

1st : Energy is used to overcome the binding force between molecules

2nd : The kinetic energy does not change

Calculate (i) The energy absorbed by the ice cubes.

[1 m]E = Pt = 600 x 60= 36000 J

(ii) The mass of ice cubes which have melted.[2 marks]

Pt = mLm = 36000/3.3 x 105 = 1.09 x 10-1 kg

Diagram 5.1 and Diagram 5.2 show the ray diagram of a man standing at two different distances in front of a concave mirror.

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What is the characteristic of the image formed in Diagram 5.1? Tick (√) the correct answer in the box provided

Real image

(b) Observed Diagram 5.1 and Diagram 5.2.(i) Compare the object distance

(ii) Compare the image distance

(iii)Compare the size of the image

Object distance in Diagram 5.1 is longer

Image distance in Diagram 5.1 is shorter

Size of image in Diagram 5.1 is smaller

(c) Based on the answer in 5(b),(i) State the relationship between object

distance and the image distance.

(ii) State the relationship between object distance and the size of the image.

Object distance larger, image distance shorter / inversely proportional

Object distance longer, size of the image smaller / inversely proportional

(d) Diagram 5.3 shows a parabolic dish that is used to receive signals from a television station.

(i) Where should the receiver be placed to obtain the strongest signal?

(i) Give one reason for your answer in 5(d)(i).

At the focal point / F

The object is at infinity / very far away @ parallel signal is reflected / converge at focal point

Diagram 6.1 shows the wave pattern when water wave moves from region A to region B in a ripple tank.

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Diagram 6.2 shows the cross-section of a ripple tank. The wavelength of the water changes as it moves from region A to region B.

(a) What is the meaning of wavelength?

The distance between two successive points which are inphase.@ Distance between two consecutive crests or trough

Based on Diagram 6.1 and Diagram 6.2,(i) Compare the wavelength between region A

and region B.

(ii) compare the incident angle, θ1 and refracted angle, θ2.

(i) compare the depth of water between region A and region B.

Wavelength in region A is longer

Incident angle is larger than refracted angle

depth of water in region A is deeper

(c) Based on answers in 6(b),(i) state the relationship between the depth of

water and the wavelength.

(i) Complete the sentence below.

As the depth increases, the wavelength increases

When water wave travels from a deep to a shallow region, the direction of propagation is refracted towards the normal.

(d) Explain why most beach resorts are built at the bay area compared to the headland.

1st : The energy of the wave spread at the bay /the wave refracted towards the normal

2nd : calmer sea / smaller amplitude

A student is running a 200 m event. Diagram 7 shows the distance-time graph to illustrate his running.

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(a) Tick (√) the correct answer in the box provided.Distance is a Scalar quantity

(i) Based on Diagram 7, calculate the speed of the student at section AB.

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(ii) Compare the speed of the student at OA and AB.

(200 – 100)24 - 14

= 10 ms-1

Speed OA < speed AB

Based on the following aspect, give suggestions on how the running time for 200 m event can be shortened.(i) The student’s attire:

Reason:

(ii) The student’s shoe:Reason:

(iii) The equipment used at the starting line

Reason:

Tight Reduce air resistance

Spike shoe /stud

Better grip

Starting block

Increase forward force / momentum

Diagram 8.1 shows a metal coated polystyrene ball hang between two metal plates, R and S.The metal plates are connected to an Extra High Tension, E.H.T. supply. A strong electric field between metal plates R and S is produced when the switch is on.

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(a) What is the meaning of electric field?

(a) When the metal coated polystyrene ball oscillates between the two plates for 3 minutes, 0.3 A of current flows in the circuit. Calculate the total charge transferred between the two plates.

A region where electric charges experience forces

Q = It = 0.3 x (3 x 60) = 54 C

The frequency of oscillation of the metal coated polystyrene ball can be increased by using one of the method listed in Table 8.1.

Based on Table 8.1, state the suitable method to increase the frequency of oscillation. (i) Diameter between the two plates:

Reason:(ii) Mass of the metal coated polystyrene ball:

Reason:(iii) Voltage of E.H.T. supply:

Reason:

Short distanceOscillates in short time / faster

Low mass

Increase the acceleration / speed

High voltageIncrease electric field

Based on the answers in (c)(i), (c)(ii) and (c)(iii), choose the most suitable method to increase the frequency of oscillation. Z

(e) The nylon thread in Diagram 8.1 is replaced with a copper thread.

(i) What happen to the motion of the metal coated polystyrene ball?

(i) Give a reason for your answer in (e)(i).

stationary

No charge on the metal coated polystrene ball // charge is earthed

Diagram 9.1 and Diagram 9.2 show two toy boats are separated at two different distances to each other due to the difference in pressure. In Diagram 9.1, the end of the rubber hose is pressed to reduce the size of the hose nozzle.

(a) What is the meaning of pressure?

Force per unit area // force/area

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(b)(i) Using Diagram 9.1 and Diagram 9.2, compare the speed of water spurting out from the rubber hose and the distance of separation between the toy boats.

• Speed of water that spurst out in Diagram 9.1 is higher

• The distance of separation between the two toy boats is Diagram 9.1 is shorter

(b)(ii) State the relationship between the speed of water spurting out and the distance of separation between the toy boats to make a deduction regarding of relationship between the speed of water and pressure..• The higher the speed of water, the

shorter the distance of separation• The higher the speed of water, the lower

the pressure

(iii) Name the physics principles involved.

Bernoulli’s principle

(c) Diagram 9.3 shows a cross section of a Bunsen burner. Using the physics principle, explain how a complete combustion can be produced by the Bunsen burner.

[4 marks]• The gas from the gas tank flow in the bunsen burner

• At the nozzle, the velocity of gas flows is very high

• A region of low pressure is produced at the nozzle

• Air is sucked in • The mixture of gas and air

producing complete combustion of gas

(d) Diagram 9.4 shows a hydrometer which is used to measure density of a liquid.You are required to modify the design in Diagram 9.4 so that the hydrometer is more sensitive and can measure wider range of liquid’s density.State and explain the modifications based on the following aspects: (i) Length of the stem(ii) Material of the hydrometer(iii) Diameter of the stem(iv) Size of the bulb(v) Number of lead shots

[10 marks]

• longer• Wide / big range // sensitive // small

scale division• Plastic // glass • Avoid corrosion• Small diameter // narrow

increase sensitivity / detect small change• Big bulb• Bouyant force / more weight of water

displaced• More number of lead shorts• Stable // balance

Diagram 10.1(a) and Diagram 10.2(a) show two identical Van de Graaff generators being charged for 1 minute and 5 minutes respectively. Diagram 10.1(b) and Diagram 10.2(b) show the deflection of the microammeter pointer when the metal dome is connected to the microammeter and a metal tap.

What is the physical quantity that can be measured by a microammeter? [1 mark]Current

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(i) Using Diagram 10.1 and 10.2, compare the time taken to charge the Van de Graaff generator, quantity of charge produced on the dome and the angle of deflection of the microammeter pointer.

The time taken to charge the Van de Graaff generator in Diagram 10.2(b) is longer (vice versa) √2 The quantity of charge produced on the dome in Diagram 10.2(b) is greater (vice versa) √3 The angle of deflection of the micrometer pointer in Diagram 10.2(b) is greater (vice versa)

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(ii) State the relationship between:*The time taken to charge the Van de Graaff generator

and the quantity of charge produced on the dome.*The quantity of charge produced on the dome and the current produced. [2 marks]

√4 Time increase, charge increase // time α charge // Q α t // q α t // Q = It //graph√5 charge increase, current increase

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(c) Diagram 10.3 shows a filament lamp. Explain why the filament in coiled shape produces more light.

√1 Length high / long / increase√2 high resistance / resistivity / R / ƿ√3 (produce / release) heat /energy / power // E = I2Rt / (V2/R)t // P = I2R / P = (V2/R)√4 heat to light // Electric → light // Electrical → light // heat → light

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(d) Diagram 10.4 shows the design of a wire-wrapped variable resistor made by a student to control the amount of current flowing through a circuit. The resistance of the variable resistor can be varied to a maximum of 10 Ω.You are required to modify the design in Diagram 10.4 so that the maximum resistance is greater than 10 Ω. State and explain the modification based on following aspects:(i) Cross-sectional area of wire used.(ii) Length of wire used(iii) Number of turns of the wire(iv) Conductivity of the slider(v) Type of wire used.[10 marks]

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Small cross sectional area

High resistance

Longer wire To increase number of turns wrapped / High resistance

5 Higher number of turns of wrapped wire

6 To increase the maximum resistance // increase resistance

High conductivity To allow current flow from the terminal to the coil

Brass / nichrome / constantan

High resistance

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Induced current

• The strength of magnetic field of the bar magnet is same

• The number of turns of the coil in 10.2 is greater

• The deflection of the galvanometer pointer in 10.2 is greater

• The number of turns of the coil is directly proportional to the size of deflection of the galvanometer pointer

• The number of turns of the coil is directly proportional with the rate of change of magnetic flux.

• The rate of change of magnetic flux is directly proportional to the magnitude of induced current

• Rotate the coil• Magnetic flux is cut by the

solenoid• Induced current is

produced

copper Low resistance / good conductor

Thick wire Low resistance

5 soft iron core6 easy to magnetized and demagnetized // reduce hysterisis

Laminated coreReduce eddy current

Closer Wind secondary coil on top of the primary coil

Reduce leakage of magnetic flux

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Distance/time

360 x 103 / 3600 = 100

(100 – 0)/10 = 10 ms-2

0(10) + ½ (10)(10)2 = 500 m

1. Low density of material

2. Light / smaller mass / small inertia

3. aerodynamic

4. Less air frictional force

5. superconductor

6. Zero resistance / no energy loss

7. 8 short coaches

8. Reduce the effect of inertia / can easily make a turn at the sharp end

9. Choose L

10.Low density material, aerodynamic shape, superconductor is used to make the magnet and 8 short coaches of fast train.

Explain how to move with a constant velocity:1. Drag = engine thrust2. Resultant force = 0

Explain how to move with an acceleration1. Engine thrust > Drag2. Resultant force is not

equal zero / F = ma

Diagram 11.1 shows a man standing infront of a curve mirror with his image shown in the mirror.(a)(i) State a light phenomenon involved in the

formation of the image.

Reflection of light

(b) Draw a ray diagram on Diagram 7.1

to show how the image is formed.[3 marks]

Image

1. A ray from object parallel to its principal axis, reflects to F

2. A ray passing through C, will reflect at the same path, C

3.Extrapolation of both rays to form image

(ii) Based on Diagram 11.1 explain how a magnified image of the man is formed by the curved mirror.

• Concave mirror is used• u < f• Reflection of light formed a virtual image• v > u• m = v/u > 1 • Height of image is bigger than height of

object

Curved mirrors are always used as security mirror in shops to watch our for shop-lifter.You are required to investigate the characteristics of curved mirrors as shown in Table 11.Explain the suitability of each characteristic of the curved mirror to be used as an effective security mirror. Determine the most suitable curved mirror that can be used as a security mirror. Give reasons for your choice.

• Convex mirror• Larger view of vision / wide field of view• Big diameter• more light / brighter image formed• High position• Wider coverage / wide view / no obstacle• Strong reflector• good reflection / clear image / sharp image• Choose S• Because it is convex mirror, big diameter,

high position and strong reflector

Diagram 11.2 shows the formation of an image by a convex lens. The focal length of the lens is 6 cm and the height of the object is 2 cm. Calculate (i) The power of the lens.(ii) The image distance.(iii)The height of the image.

P = 1/f = 1/0.06 = 16.67 D

(ii) 1/f = 1/u + 1/v1/v = 1/6 – 1/9 = 9 – 6

54v = 18 cm

(iii) m = 18/9 = h/2 = 4