O Level Physics 5054 Paper 22, May/June 2024

State how Fig. 1.2 shows that, during the collision, trolley B has a uniform acceleration.

Describe how the graph in Fig. 1.2 shows that the magnitude (size) of the acceleration of trolley B is larger than the magnitude of the deceleration of trolley A.

Calculate the acceleration of trolley B when $t=0.40\text{ s}$.

The mass of trolley A $=0.80\text{ kg}$. The mass of trolley B $=0.60\text{ kg}$. Show that momentum is conserved in the collision.

In another collision between the same trolleys, the rod and modelling clay are not present. Trolley A hits trolley B with the same initial speed. Explain why the force between the trolleys is larger in this collision.

Show that the mass of water in the pool is approximately $6700\text{ kg}$.

Define 'pressure'.

Calculate the pressure on the base of the pool due to the water.

The water in the pool is initially at a temperature of $10{}^{\circ }\text{C}$. The temperature rises when $5.1\times {10}^8\text{ J}$ of energy is transferred to the water. The specific heat capacity of water is $4200\text{ J}\mathrm{/}(\text{kg}{}^{\circ }\text{C})$. Calculate the final temperature of the water.

Explain, in terms of the movement of particles, how evaporation causes cooling.

Changes to factors in the environment of the swimming pool can cause an increase or decrease in the amount of evaporation from the surface of the water. State two changes to environmental factors that increase the amount of evaporation from the surface of the water.

Complete Fig. 3.2 to show the useful transfer of energy from the Sun to the battery.

Explain why the battery takes a long time to charge on a cloudy day.

After use, the outside surface of the cell phone is warm. When switched off, the cell phone cools down. Name and describe the three processes by which thermal energy is transferred as the cell phone cools down.

It takes $4.5\text{ hours}$ to charge the battery with an average current of $300\text{ mA}$. Calculate the quantity of charge that enters the battery. Give the unit of your answer.

Fig. 4.1 shows light passing through a triangular glass prism. State the value of the angle of incidence at point P.

Draw the normal and the angle of incidence at point R. Label the angle of incidence.

State two conditions needed so that no light refracts from the glass into the air at point Q.

Information is sent across the internet using pulses of visible light through long, thin glass fibres and electrical signals through copper wires. State the name of one other type of electromagnetic radiation used to transmit information through long, thin glass fibres.

Suggest two advantages of using glass fibres rather than copper wires to transmit information from the internet.

On Fig. 5.1, complete the labels on the diagram.

Explain why the balloon stays negatively charged for a long time.

Rubbing the balloon causes the temperature of the air inside it to rise. Explain, in terms of the particles of air, why the volume of the balloon increases when the temperature of the air rises.

State Ohm’s law.

Explain how the graph lines in Fig. 6.2 show that Ohm’s law applies to the LDR.

Use values from Fig. 6.2 to explain the effect of light on the resistance of the LDR.

With the lamp switched on, the current in the LDR is $0.050\text{ A}$. Determine the current in the fixed resistor.

Calculate the electromotive force (e.m.f.) of the cell.

A plotting compass contains a needle. The needle is a small magnet that can rotate about its centre. Fig. 7.1 shows the plotting compass placed close to a bar magnet. On Fig. 7.1 mark the magnetic poles on the bar magnet.

There is a piece of paper underneath the magnet. Describe how the compass is used to plot the magnetic field line that passes from one pole to the other and through P.

Describe how to use the compass in Fig. 7.1 to determine the direction of the magnetic field at P.

Fig. 7.2 shows the apparatus a student uses to produce an alternating current (a.c.). The magnet is moved into and out of the coil. Explain why a current is produced when the magnet moves.

Describe the movement of the magnet that produces an a.c. of frequency $0.50\text{ Hz}$.

Describe how the centre-zero ammeter shows the current is a.c. rather than d.c. (direct current).

Explain why increasing the frequency of the a.c. produced also increases the magnitude (size) of the a.c produced.

State what is meant by ‘a supernova’.

Describe how a protostar forms inside a nebula.

Our Sun is in a circular orbit around a black hole at the centre of our galaxy. State the name of the galaxy that contains our Sun.

State what is meant by a light-year.

The time taken for one complete orbit of our Sun around the black hole is $7.3\times {10}^{15}\text{ s}$. The distance from our Sun to the black hole is $26000\text{ light-years}$. $1\text{ year}=3.2\times {10}^7\text{ s}\text{speed of light}=3.0\times {10}^8\text{ m}\mathrm{/}\text{s}$ Calculate the speed of our Sun as it orbits the black hole. Show your working and give your answer in $\text{m}\mathrm{/}\text{s}$.

Describe what is meant by ‘spontaneous’ emission.

Describe the composition of an alpha particle.

Alpha particles are detected using the tracks shown in a cloud chamber or by the sparks produced in a spark counter. Describe the structure of either a cloud chamber or a spark counter. Include a labelled drawing of the apparatus.

Describe how the emission of alpha particles is shown as random in the apparatus you described in (c)(i).

A radioactive source produces 120 tracks in one minute in a cloud chamber. $6.0\text{ hours}$ later, the same source produces 15 tracks in one minute. Without the source present, no tracks are produced. Calculate the half-life of the radioactive isotope in the source.