OCR GCSE Physics B (21st Century) Paper 3 June 2025 question paper

The distance travelled from A to C is 5000 m.

Find the distance from A to B.

Use:

• Fig. 1.1

• a ruler.

When the boat leaves A, the time is 09:23. When the boat reaches B, the time is 09:53.

Calculate the average speed of the boat for its journey from A to B.

Use the Equation Sheet.

Give your answer in m / s.

Average speed =........ m / s

Fig. 1.2 shows the speed–time graph for the boat for a short period.

Calculate the acceleration of the boat.

Use Fig. 1.2.

Acceleration =........ m / s²

The boat has a force acting on it from the wind.

Which of these is a typical value for the speed of wind?

Tick (✓) one box.

In the 1930s, scientists experimented with elements and split their nuclei.

Complete the sentences about splitting the nucleus.

Use words from the list.

fission fusion negative

power stable unstable

The nuclei of certain elements can be split into two smaller nuclei because they

are........

The process is called nuclear........

Suggest why Enrico Fermi’s hypothesis was believed in 1934.

Explain why, by 1940, more scientists had confidence in the theory that nuclei can be split.

Use information from the table to support your answer.

When uranium nuclei split, neutrons are released and a chain reaction happens.

Which statement correctly explains how a chain reaction happens?

Tick (✓) one box.

Which two statements describe how the energy is released when uranium nuclei split?

Tick (✓) two boxes.

A force is applied to a spring.

There is a linear relationship between the force and the extension of the spring.

Complete the sentence to describe a linear force-extension relationship.

In a linear system, for each 1 N of force added,........

A spring has a spring constant of 15 N / m.

Calculate the energy stored when its extension is 0.01 m.

Use the Equation Sheet.

Give your answer in standard form.

Light and sound both travel as waves.

The diagram shows a ray of white light directed at a plane mirror.

Draw on the diagram:

• the reflected ray of light

• the normal, labelled N

• the angle of incidence, labelled i

• the angle of reflection, labelled r.

Which two of these words can be used to describe light waves?

Tick (✓) two boxes.

D raw lines to connect each medium a sound wave is travelling in with its correct speed.

Marie Curie discovered radioactive elements by extracting them from their ores. Her notebook became contaminated with radium and is still radioactive today.

The graph shows the activity of a sample of radium from approximately 4000 years ago until now.

Find the half-life of radium.

Use the graph.

The radium that remains on Marie Curie’s notebook has an activity today of around 600 cps.

The activity of the radium that remains on the notebook will decrease in the future.

Calculate the activity of the radium that remains on the notebook after 3 further half-lives.

Calculate the fraction of the number of nuclei that will decay in 3 half-lives.

Handling the notebook is hazardous to health.

Compare how hazardous handling the notebook was 100 years ago to how hazardous it is today.

A permanent magnet and a coil of wire are used in a speaker as shown in Fig. 6.1.

Fig. 6.2 shows a cross-section view of the permanent magnet along X–X.

Draw four lines to show the magnetic field of the permanent magnet on Fig. 6.2.

Include arrows to show the direction of the magnetic field of the permanent magnet.

Fig. 6.3 shows one coil of wire around the centre of the permanent magnet.

When an alternating current flows in the coil of wire, the wire experiences a force.

Explain why there is a force on the coil of wire.

Explain how the force on the coil of wire produces sound from the speaker with the same frequency as the alternating current.

Calculate the force on the one coil of wire.

• The magnetic flux density is 1.2 T.

• The current is 0.3 A.

• The circumference of the coil of wire is 5 cm.

Use the Equation Sheet.

Suggest three ways to increase the size of force on the coil of wire in the speaker.

An exercise bike is connected to a magnet which turns when the wheels go round.

When the exercise bike is ridden, the magnet turns inside a coil of wire. This induces a potential difference in a circuit.

What must the coil of wire be connected to so that a direct current is produced in the circuit? Tick (✓) one box.

The graph shows the potential difference-time graph for the exercise bike.

Which feature of the potential difference-time graph shows that a direct current is produced?

Tick (✓) one box.

Define a renewable energy resource.

Explain whether the electricity produced by riding the bike has come from a renewable or non-renewable source.

Emperor penguins dive very deep in the sea.

Explain why the pressure on an object increases as its depth in the sea increases.

Use ideas about forces in your answer.

An emperor penguin dives to a depth of 400 m.

Calculate the pressure on the penguin.

• The approximate density of seawater is 1020 kg / m³.

• The gravitational field strength is 10 N / kg.

Use the Equation Sheet.

Give your answer in kPa.

Colder water has a higher density.

Explain the effect on your answer to (b)(i) if the penguin still dives to 400 m but the water is colder.

Fig. 8.1 shows an emperor penguin partially submerged on the surface of the water.

Explain why the water exerts a net force upwards on the penguin.

Explain the trends in the data shown in the table.

Explain why the penguin will sink at a depth of 100 cm if it is not swimming.

Use the data in the table.

The approximate density of seawater is 1020 kg / m³.

The diagram shows a gas thruster.

The gas thruster releases a gas to change the orbit of a satellite.

The satellite is in a stable circular orbit at a height of about 500 km above the Earth. The gas thruster moves the satellite about 3 km further away from Earth. The gas thruster is turned off and the satellite settles into a new stable circular orbit.

Compare the force of gravity at the two orbits.

Explain the difference in the speed of the satellite in its new orbit compared to its speed in the original orbit.

Explain why the satellite is accelerating when it is in a stable circular orbit.

When the satellite moves to its new orbit its momentum is 9 144 000 kgm / s.

Calculate the velocity of the satellite in its new orbit.

The mass of the satellite is 1200 kg.

Use the Equation Sheet.

Velocity =........ m / s