Cambridge IGCSE Physics - 0625 - Supplement Paper 2 2012 Winter Zone 3

Two stones of different weight fall at the same time from a table. Air resistance may be ignored.
What will happen and why?

[Table]
| | what will happen | why |
|---|------------------------------------------|-----------------------------------------|
| A | both stones hit the floor at the same time | acceleration of free fall is constant |
| B | both stones hit the floor at the same time | they fall at constant speed |
| C | the heavier stone hits the floor first | acceleration increases with weight |
| D | the heavier stone hits the floor first | speed increases with weight |

The speed-time graph shown is for a bus travelling between stops. Where on the graph is the acceleration of the bus greatest? [Image_1: Speed-Time Graph]

A large bag of feathers and a steel block balance each other on some scales.
What does this show about the masses and the weights of the bag of feathers and the steel block?
A. It shows that the masses are equal and the weights are equal.
B. It shows that the masses are equal, but the weights might be different.
C. It shows that the masses might be different and the weights might be different.
D. It shows that the weights are equal, but the masses might be different.

Which row identifies quantities that are measured in newtons?

[Table_1]

| | electromotive force (e.m.f.) | mass | weight |
|---|--------------------------|------|--------|
| A | no | no | yes |
| B | no | yes | yes |
| C | yes | no | no |
| D | yes | yes | no |

A liquid has a density of 0.80 \text{g/cm}^3.
Which could be the volume and mass of this liquid?
[Table_1]

The diagram shows sections of four objects of equal mass. The position of the centre of mass of each object has been marked with a cross.

Which object is the most stable?

A large parcel is on a horizontal conveyor belt. The conveyor belt moves the parcel towards a lorry.



The parcel travels towards the lorry at a constant speed. Only two horizontal forces act on the parcel: air resistance, and friction with the conveyor belt.

Which row correctly compares the directions and the sizes of these two forces?

[Table_1]

A power station uses nuclear fission to obtain energy. In this process, nuclear energy is first changed into
A. chemical energy.
B. electrical energy.
C. gravitational energy.
D. thermal (heat) energy.

A person lifts boxes of equal weight on to a platform.

Which quantity will not affect the work done by the person?
A the height of the platform above the ground
B the number of boxes lifted
C the time taken to lift the boxes
D the weight of the boxes

A skier walks from the bottom of a ski slope to the top and gains 10000 J of gravitational potential energy. She skis down the slope. At the bottom of the slope, her kinetic energy is 2000 J.
How much energy was converted into thermal energy and sound energy as the skier moved down the slope?
A 2000 J
B 8000 J
C 10000 J
D 12000 J

The diagram shows a mercury barometer. Which distance is used to calculate the pressure of the atmosphere?
A 25 cm
B 75 cm
C 80 cm
D 100 cm

A dam across a lake is divided into two sections by a rock. Section X is longer than section Y but the two sections are otherwise identical. The water in the lake by the dam is the same depth everywhere. The diagram shows a view from above of the lake and the dam. [Image_1 showing lake, sections X and Y, and rock]
The water creates a force on each section of the dam and a pressure on each section of the dam.
Which statement is correct?
A The force on X equals the force on Y.
B The force on X is less than the force on Y.
C The pressure on X equals the pressure on Y.
D The pressure on X is less than the pressure on Y.

A car tyre contains a constant volume of air.
During use, the air gets hotter and the air pressure increases.
What explains this increase in pressure in terms of the motion of air molecules?
[Table_1]

The table lists the melting points and the boiling points of four different substances. Which substance is a liquid at 0°C?

[Table_1]

melting point/°C | boiling point/°C
A -219 | -183
B -7 | 58
C 98 | 890
D 1083 | 2582

A student wishes to calibrate a mercury-in-glass thermometer with a °C scale.
Which values should she use for the lower fixed point and for the upper fixed point?

[Table_1]

The graph shows the temperature of a substance as it is heated steadily. In which part of the graph is the substance boiling?

Four blocks, made from different materials, are each heated so that they have the same increase in internal energy.
Which block has the smallest thermal capacity?

A convector heater is fixed to a wall.
Which diagram shows how warm air near the heater moves because of convection in the air?

A double-glazed window consists of two panes of glass with a vacuum between them.
The vacuum reduces the amount of thermal energy transferred through the window.

Which row shows how much thermal energy is transferred through the vacuum by conduction, by convection and by radiation?
[Table_1]

The diagram shows a water wave in a ripple tank.
Which line represents a wavefront?

Which statement about radio waves is correct?
A They travel as longitudinal waves.
B They travel at the same speed as sound waves.
C They travel by means of molecular vibration.
D They can travel through a vacuum.

The converging lens in a camera is used to make an image on a film.
At which labelled point could a large object be placed so that it makes a smaller image?

A ray of light in water is incident on the surface. The angle of incidence is much smaller than the critical angle.
[Image_1: Diagram of a ray of light passing from water to air with labels 'air', 'water', and 'ray of light'.]

What happens to this ray?
A It is completely reflected.
B It is completely refracted.
C It is partially reflected and partially refracted.
D It is refracted at an angle of refraction of 90°.

Sound waves may cause an echo.
What happens to sound waves to cause an echo and what is the nature of sound waves?

[Table_1]

Table:
| | what an echo is caused by | nature of sound waves |
|------------|---------------------------|-----------------------|
| A | reflection | longitudinal |
| B | reflection | transverse |
| C | refraction | longitudinal |
| D | refraction | transverse |

In a test, a car horn is found to be too loud and the pitch of the note is too high.
What information does this give about the amplitude and the frequency of the sound wave produced?
[Table_1]

Which row shows whether iron and steel are ferrous or non-ferrous?
[Table_1]
Table 1:
iron | steel
------|------
A | ferrous | ferrous
B | ferrous | non-ferrous
C | non-ferrous | ferrous
D | non-ferrous | non-ferrous

The N pole of a magnet repels one end of bar X.

What happens when the other end of bar X is placed near to the poles of the magnet?

[Table_1]
| | other end near N pole | other end near S pole |
|------------|-----------------------|-----------------------|
| **A** | attracts | attracts |
| **B** | attracts | repels |
| **C** | repels | attracts |
| **D** | repels | repels |

Which is the worst electrical conductor?
A. aluminium
B. carbon (graphite)
C. iron
D. sulfur

The circuit shows a 24V battery connected to two resistors in series.
The reading on the ammeter is 2.0A and the reading on the voltmeter is 8.0V.
What is the resistance of resistor R?
A 0.25Ω B 4.0Ω C 10Ω D 16Ω

A relay allows a small current in one circuit to control a different circuit.
Which type of force is produced by the small current to activate the relay?

A. electrical
B. frictional
C. gravitational
D. magnetic

The diagram shows a circuit containing two identical lamps.
Which switches must be closed to light both of the lamps?
A. P and Q only
B. P and R only
C. Q and R only
D. P, Q and R

The diagram shows a potential divider circuit.
The temperature of the thermistor increases.
What happens to the resistance of the thermistor, and what happens to the reading on the voltmeter?

| resistance of thermistor | voltmeter reading |
|-------------------------|-------------------|
| A decreases | decreases |
| B decreases | increases |
| C increases | decreases |
| D increases | increases |

An electric oven is connected to the mains supply using insulated copper wires. The wires become very warm.

What can be done to prevent so much heat being produced in the connecting wires?

A Use thicker copper wires.
B Use thinner copper wires.
C Use thicker insulation.
D Use thinner insulation.

Which graph shows how the voltage of a simple a.c. generator varies with time? [Image_1: Graphs labeled A, B, C, D showing different voltage vs. time graphs]

In the construction of a transformer, which items must be included?
A. an iron core and a permanent magnet
B. an iron core and two coils of wire
C. a steel core and a permanent magnet
D. a steel core and two coils of wire

The metal filament shown is heated by passing a current through it. This makes it hot and it releases electrons.
[Image_1: Diagram of filament in vacuum]
What is the name of this process of releasing electrons?
A. convection
B. evaporation
C. radioactive emission
D. thermionic emission

How do the ionising effect and the penetrating ability of $\alpha$-particles compare with those of $\beta$-particles and $\gamma$-rays?

[Table_1]

A student is investigating how the radiation from a radioactive source changes with time.
The table shows the results from the detector.
[Table_1]
The experiment is repeated by other students, who also measure the count-rate every two minutes.
The half-life of the source is known to be exactly two minutes.
Why is the measured count-rate always higher than half the previous value?
A Radioactive emissions occur randomly with time.
B The detector used is very close to the source.
C There is background radiation present.
D The radioactive source is decaying.

Which of the following is not a charged particle?
A. \(\alpha\)-particle
B. \(\beta\)-particle
C. neutron
D. proton