O Level Physics 5054 Paper 22, Oct/Nov 2025

Using Fig. 1.1, determine: the speed of the car at time $t=0$

Using Fig. 1.1, determine: the distance travelled by the car between the driver seeing the obstruction at $t=5.7\text{ s}$ and the car beginning to slow down

Using Fig. 1.1, determine: the distance travelled by the car between $t=0$ and $t=11.2\text{ s}$.

The speed of the car affects both the thinking distance and the braking distance. State one factor that affects only the braking distance of the car. Explain how a change in this factor increases the braking distance.

The container reaches terminal velocity before it hits the bottom of the lake. Explain, in terms of the forces on the container, the motion of the container through the water until it reaches terminal velocity.

The container falls through a vertical distance of $32\text{ m}$ before it hits the bottom of the lake. The container and instruments have a total mass of $74\text{ kg}$. Calculate the energy transferred from the gravitational potential energy store of the container.

State the principle of conservation of energy.

Work is done to transfer energy from the gravitational potential energy store as the container falls at terminal velocity. Describe, in terms of the work done, how the energy is transferred from the gravitational potential energy store to one other energy store in the water.

Calculate: the mass of the water that hits the wall in $1.0\text{ s}$

Calculate: the horizontal momentum of the water that hits the wall in $1.0\text{ s}$.

The horizontal momentum of the water decreases to zero when the water hits the wall. None of the water bounces back from the wall. Explain why the momentum calculated in (a)(ii) is equal in size to the horizontal force exerted on the water by the wall.

Explain, in terms of Newton’s third law, why there is a horizontal force exerted on the wall by the water.

The pump that forces the water to flow through the hose is adjusted, and the speed of the water leaving the hose doubles. Explain why the force exerted by the water on the wall increases by a factor of 4.

Explain how Fig. 4.1 shows that the melting temperature of the wax is $63{}^{\circ }\text{C}$.

As the temperature of the wax increases, the energy in the internal energy store increases. The mass of the wax in the test-tube is $0.040\text{ kg}$ and its temperature at time $t=0$ is $21{}^{\circ }\text{C}$. The specific heat capacity of wax is $2100\text{ J}\mathrm{/}(\text{kg}{}^{\circ }\text{C})$. Using Fig. 4.1, determine the increase in the energy in the internal energy store of the wax between $t=0$ and $t=220\text{ s}$. Show your working.

Describe what happens to the motion of the molecules of the solid wax as the internal energy of the wax increases.

When the wax reaches its melting temperature, energy continues to be transferred thermally to the wax. Describe, in terms of the forces between particles, why energy is required to melt the wax.

Fig. 5.1 represents the electromagnetic spectrum divided into the seven main regions. The regions are arranged from left to right in order of increasing wavelength. On Fig. 5.1: • indicate the microwave region by marking it with the letter M • indicate the ultraviolet region by marking it with the letters UV.

The frequency of the microwaves used by some satellite television systems is $12\text{ GHz}$. The speed of microwaves in a vacuum is $3.0\times {10}^8\text{ m}\mathrm{/}\text{s}$. Calculate the wavelength of these microwaves in a vacuum.

Describe how microwaves are used in satellite television systems.

All microwave ovens have a switch that turns the oven off when the door is opened. Suggest why it is important for a microwave oven to switch off when the door is opened.

Describe how a direct current differs from an alternating current (a.c.).

Fig. 6.1 represents the motor circuit. Point P is a point in the circuit between the motor and the positive terminal of the power supply. Point P is shown to the left of the motor in the circuit diagram. During a time of $120\text{ s}$, the current in the circuit at point P is $41\text{ A}$. Calculate the charge that flows through point P in the time of $120\text{ s}$.

The current in the circuit is due to the flow of electrons. Each electron carries a charge of magnitude $1.6\times {10}^{-19}\text{ C}$. State the direction which the electrons move past point P and determine the number of electrons that pass point P in $1.0\text{ s}$.

The power supply for the electric car is a number of batteries, each made from a large number of identical cells. The e.m.f. (electromotive force) of each cell is $3.7\text{ V}$. Define the term ‘electromotive force’.

Each battery consists of 92 cells in series. Calculate the e.m.f. of one battery.

The power supply is made by connecting 85 of these batteries in parallel. State the e.m.f. of the power supply.

The kettle is switched on. Calculate the current in the heater.

The manufacturer of the kettle states that the cable for the kettle is safe for currents that are smaller than $15\text{ A}$. The wiring in the mains power supply in the wall is safe for currents that are smaller than $20\text{ A}$. The fuses available for the kettle have the ratings shown. $3\text{ A}5\text{ A}7\text{ A}10\text{ A}13\text{ A}15\text{ A}18\text{ A}20\text{ A}25\text{ A}$ State which of these fuses is the most appropriate. Explain why it is the most appropriate.

There are three wires in the cable that connects the kettle to the mains power supply: • the earth wire • the live (line) wire • the neutral wire. The wires are all correctly connected. State the name of the wire that the fuse is connected into. Explain why the fuse is connected into this wire.

The insulation on the live wire is damaged so that the wire is exposed. Explain what happens when the exposed live wire touches the metal outer casing.

The kettle is switched on for a total time of $34\text{ h}$ during one year. The cost of electricity is $\mathrm{\$}0.32$ per kilowatt-hour (kWh). Calculate the cost of using the kettle during the year.

State one way in which the compositions of the atoms of all lithium isotopes are the same.

State one way in which the composition of a lithium atom of one isotope is different from the composition of a lithium atom of a different isotope.

Fig. 8.1 is a diagram that represents a neutral atom of a radioactive isotope of lithium (Li). There are three electrons in orbit around the nucleus. The nuclide symbols for isotopes of lithium are represented as ${}_Y^X\text{Li}$ where $X$ and $Y$ are numbers. Determine the values of $X$ and $Y$ for the isotope represented by Fig. 8.1.

An ion of this isotope of lithium has a single positive charge and is represented as (${}_Y^X{\text{Li}}^{+}$). Describe how the diagram that represents this ion differs from Fig. 8.1.

Radioactive isotopes emit nuclear radiation which can affect living things. State one damaging effect of nuclear radiation.

The emission of radioactive radiation from an unstable isotope is described as random and spontaneous. State what is meant by ‘random’ and what is meant by ‘spontaneous’.

The speed of light in a vacuum is $9.5\times {10}^{12}\text{ km}\mathrm{/}\text{year}$. The Sun is $26000\text{ light-years}$ from the centre of the Milky Way. Determine the distance from the Sun to the centre of the Milky Way in kilometres (km).

It takes the Sun $2.3\times {10}^8\text{ years}$ to complete one orbit around the centre of the Milky Way. Calculate the speed $v$.

Astronomical observations suggest that, at the centre of the Milky Way, there is a black hole. Black holes are produced from red supergiants. Near the end of its life, a massive star becomes a red supergiant. Describe what happens inside the star as it becomes a red supergiant.

Describe how a red supergiant produces a black hole.

Describe how the heaviest elements are produced.