SMJK PEREMPUAN CHINA PULAU PINANG

PEPERIKSAAN PERCUBAAN SPM 2011

4531/2

PHYSICS

Kertas 2

Sept 2011

2½ jam Dua jam tiga puluh minit

DO NOT OPEN THIS QUESTION PAPER UNTIL YOU ARE TOLD TO DO SO.

Section Question Marks

allocated

Marks

A

1 4

2 7

3 8

4 6

5 6

6 9

7 10

8 10

B

9 20

10 20

C

11 20

12 20

Total

This question paper consists of 16 printed pages

1. This question paper consists of three

sections: Section A, Section B and

Section C.

2. Answer all questions in Section A. Write

your answer for Section A in the spaces

provided in the question paper. 3. Answer any one question from Section B,

and any one question from Section C. Write

your answer for Section B and Section C on

the writing paper provided by the

invigilators. Answer questions in Section B

and Section C in detail. You may use

equations, diagrams, tables, graphs and other

suitable methods to explain your answer.

4. The time suggested to answer Section A is 90

minutes, Section B is 30 minutes and Section

C is 30 minutes.

5. You may use a non-programmable scientific calculator.

6. Hand in this question paper at the end of the

examination.

Name : ___________________________

Class : __________________________

2

SECTION A (60 marks)

1. Figure 1 shows a micrometer screw gauge used to measure the diameter of a marble.

a. Name the part labeled X. [1 mark]

__________________________________________________________________

b. What is the diameter of the marble? [1 mark]

__________________________________________________________________

c. State two precautions that can be taken when using micrometer screw gauge. [2 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

2. The mass of a huge balloon without inflating with gas is 400 kg. It is then filled with

2500 m3 of helium gas. The density of helium gas and air are 0.16 g m

-3 and 1.3 kg m

-3

respectively.

a. What is the total weight of the balloon? [3 marks]

Figure 1

3

b. What is the weight of the air displaced? [2 marks]

c. Explain what will happen to the balloon when it is released. [2 marks]

__________________________________________________________________

__________________________________________________________________

3. A doctor injected some gamma ray source of radioactive liquid into a patient to check

whether the kidneys of the patient function normally. The half-life of the radioactive

source is 8 days. The radioactive source will flow through the patient’s kidneys. If the kidneys are functioning normally, the radioactive substances will be expelled in 20

minutes. The change of radioactivity in the kidneys with time is as shown in the figure

below.

a. Based on Figure 2, why does the doctor suspect that one of the kidneys is not functioning normally? [2 marks]

_________________________________________________________________

_________________________________________________________________

b. Give two reasons why a gamma source is more suitable to be used in this case? [2 marks]

__________________________________________________________________

__________________________________________________________________

Figure 2

4

c. The half-life of the radioactive source used must not be too short. Explain why.

[2 marks]

__________________________________________________________________

__________________________________________________________________

d. The initial radioactivity of the substance is 600 000 counts per second. What is the

radioactivity of the substances after 40 days? [2 marks]

4. Figure 3 shows a natural phenomenon.

a. Name the phenomenon in Figure 3. [1 mark]

____________________________________________________________________

b. Name two physics phenomena involved in the phenomenon above. [2 marks]

____________________________________________________________________

c. Explain briefly how the phenomenon occurs. [3 marks]

____________________________________________________________________

____________________________________________________________________

____________________________________________________________________

____________________________________________________________________

____________________________________________________________________

Figure 3

5

5. Figure 4 shows a rectangular coil placed in a circular wire coil. Both the rectangular

coil and the circular wire coil are connected to two separate direct current voltages.

a. State the direction of the current flowing in the rectangular coil when switch S is

closed. [1 mark]

__________________________________________________________________

b. (i) Describe the motion of the rectangular coil, XY when switch S is closed.

Explain your answer. [2 marks]

________________________________________________________________

________________________________________________________________

(ii) State two ways of increasing the effect of this motion. [2 marks]

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

c. The D.C. voltage source between c and d is replaced with an alternating current source. Describe the change in the motion of the rectangular coil, XY. [1 mark]

__________________________________________________________________

Figure 4

6

6. A longitudinal wave is traveling from left to right in a medium. Figure 5.1 shows the

equilibrium positions of some particles, A to K, in the medium. Figure 5.2 shows the positions of the particles at a certain time, t when the wave is passing through them.

a. Which point is the centre of compression? [1 mark]

__________________________________________________________________

b. Which point is the centre of rarefaction? [1 mark]

__________________________________________________________________

c. Table 1 shows the displacement of particle A at time t. (displacement to the right

is taken to be positive)

i. Using Figure 5.1 and 5.2, find the displacements of the other particles and complete Table 1. [2 marks]

Particle A B C D E F G H I J K

Displacement/cm 0

Figure 5.2

Figure 5.1

Table 1

7

ii. In Figure 5.3, draw a graph to show the displacements of the particles along the

wave at time t. [2 marks]

iii. Find the wavelength of the wave. [1 mark]

iv. If each particle takes 0.25 s to complete one oscillation, find the speed of the wave. [2 marks]

Figure 5.3

8

7. Figure 6.1 shows an electronic circuit. A relay coil will close switch X if the output of

the NOT gate is high.

a. What will happen to the resistance of the thermistor and the output of NOT gate

when the thermistor is heated up? [2 marks]

__________________________________________________________________

__________________________________________________________________

b. Explain what will happen resulting from your answer in 7(a). [2 marks]

__________________________________________________________________

__________________________________________________________________

c. Suggest one application for the circuit in Figure 6.1. [1 mark]

__________________________________________________________________

d. Figure 7.2 shows a combination of logic gates circuit. Table 2 is the truth table for

Figure 7.2.

i. Name logic gates M and N. [2 marks]

M: ______________________ N: ______________________

ii. Complete Table 2. [3 marks]

A B X Y Z

0 0

0 1

1 0

1 1

Figure 6.1

Figure 7.2 Table 2

Thermistor

10 kΩ

Relay coil

Siren

12 V

P

M

N

Switch X

9

8. Car A of mass 2000 kg moves with a velocity of 36 km h-1

and hits car B of mass

2400 kg which is stationary. The collision time between the two vehicles is 0.5 s. After collision, car A stops immediately and car B moves for 5 seconds in the initial

direction of the car before it stops.

a. Determine the velocity of car B just after collision. [2 marks]

b. What is the change of momentum of car A? [2 marks]

c. Calculate the impulsive force acting on car A during collision. [2 marks]

10

d. How far will car B go before it stops? [2 marks]

e. Calculate the value of the friction experienced by car B. [2 marks]

11

SECTION B (20 marks)

9. Figure 8.1 shows the water levels in a Venturi tube.

a. What is meant by Bernoulli’s principle? [1 mark]

b. Compare the speed of water flow, the water levels and the water pressure at

positions A, B and C. State the relationship between water pressure and the water level. Deduce the relationship between water pressure and the speed of water flow.

[5 marks]

c. Figure 8.2 shows two ships moving parallel to each other at the same speed.

Explain what will happen to the two ships. [4 marks]

d. You are a pilot. Based on your physics knowledge, explain the required modifications to an airplane so it could lift and move easily in the air. Your

modifications should focus on the following aspects:

i. the material used to construct the body,

ii. the shape and features of the airplane. [10 marks]

Figure 8.1

B

Figure 8.2

C A

Ships

12

10. The national grid is an important system which ensures that the electric power supply

is always continuous. After electrical energy is generated at the power generator, the electrical energy will be transferred through a few substations that contain

transformers before reaching the consumers. Table 3.1 shows the current and

potential difference of the electrical energy before and after passing through

substation A during the transfer of electrical energy.

Transfer of electrical energy

Before passing substation

A

After passing substation

A

Current/A 80 15

Potential difference/V 25 000 132 000

Table 3.2 shows the current and the potential difference of the electrical energy before and after passing through substation B during the reception of electrical energy by the

consumers.

Transfer of electrical energy

Before passing substation

B

After passing substation

B

Current/A 15 60

Potential difference/V 132 000 33 000

a. What is meant by potential difference? [1 mark]

b. Based on tables 3.1 and 3.2, compare the change to the current, the potential difference and the electrical power of the electrical energy after passing through

substation A and B. Deduce the relation between the change in potential

difference and the change in current. Describe the relation between the change in potential difference and the change in electrical power. [5 marks]

Table 3.1

Table 2.1

Table 3.2

13

c. Nuclear power is an efficient way to generate electricity. The figure below shows

a nuclear power generator which generates electricity to a town.

Explain how a nuclear power plant generates electricity. [4 marks]

d. Pylons play an important role in transferring and receiving electrical energy.

Explain how an electricity company can improve the transmitting system in the

following aspects: i. The safety features that are needed to build the poles.

ii. The properties of the cables that are used. [10 marks]

Figure 9.2

Figure 9.1

Pressurizer

Generator

Reactor

vessle

Steam

generator Turbine

Condenser

CO2

14

SECTION C (20 marks)

11. Table 4 shows the characteristics of some materials that can be used for making a

heating element.

Material Melting

point/°C

Resistance/Ω Rate of

oxidization

Length of

heating

element/cm

P 500 25 Low 25

Q 500 100 High 15

R 50 50 Low 30

S 350 75 Low 15

T 200 25 High 10

a. What is meant by resistance? [1 mark]

b. You are assigned to investigate the characteristics of the materials in Table 4 for

making of heating element in an electric kettle. Explain the suitability of each characteristic and determine the most suitable material to be used. Justify your

answer. [10 marks]

c. Figure 10 shows a circuit for determining the electromotive force and the internal

resistance of a dry cell.

i. Sketch a graph of potential difference against current for the circuit. [2 marks]

ii. Describe how you would determine the internal resistance and the

electromotive force of the dry cell from the graph in 11c(i). [2 marks] iii. The total resistance for both the resistor and the rheostat in the circuit is 5 Ω.

The readings of the voltmeter before and after the switch is being switched on

are 6 V and 5 V respectively. Calculate the current, I in the circuit and the

internal resistance, r of the dry cell. [5 marks]

Table 4

Figure 10

15

12. Figure 11.1 shows the arrangement of apparatus to determine the specific heat

capacity of aluminium solid. Table 5 shows the materials used in the experiment.

a. State the meaning of specific heat capacity. [1 mark]

b. You are assigned to investigate the materials shown in Table 5 to be used to

determine the specific heat capacity of aluminium in Figure 11.1.

Material

Set of apparatus

Thermal

conductivity

of plate X

Specific heat

capacity of liquid Y

(J kg-1

°C-1

)

Material Z

Power of

heater (W)

P High 4200 Ice 12

Q Low 2100 Paper 48

R High 600 Cotton 24

S Low 600 Cotton 48

T Moderate 4200 Paper 24

Explain the suitability of each material in Table 5 then determine the most suitable

set of apparatus to be used to determine the specific heat capacity of aluminium.

Justify your choice. [10 marks]

Figure 11.1

Table 5

16

c. Figure 11.2 shows a graph of temperature against time taken for heating 500 g of a

liquid by using a heater of 50 W.

i. What is the boiling point of the liquid? [1 mark]

ii. Determine the specific heat capacity of the liquid. [3 marks]

iii. Calculate the latent heat of vaporization of the liquid. [2 marks] iv. At the 10

th minute, the vapour is flowed into a beaker that contains 1 kg of

water at 25 °C. What is the final temperature of mixture?

(Specific heat capacity of water = 4200 J kg-1 ºC

-1) [3 marks]

Figure 11.2

Prepared by:

P.Y. Chan

Checked by:

Approved by: