Edexcel IGCSE Physics Physics Paper 2 January 2022 question paper 4PH1/2PR

The table lists four methods of generating electricity and four energy stores.

The energy store of the initial energy resource decreases when electricity is being generated.

Complete the table by placing one tick (✓) in each row to show which energy store decreases.

State which method of generating electricity in the table does not use a renewable energy resource.

State two disadvantages of using wind turbines to generate electricity.

Cricket is a sport played with bats and balls.

A cricket player hits a ball with a bat. Before the ball is hit, it is moving to the left with a momentum of 4.2 kg m/s.

The bat is in contact with the ball for 0.012 s.

After the ball is hit, it moves to the right with a momentum of 6.7 kg m/s.

Calculate the mean force the bat exerts on the ball and state the direction of the force.

State the magnitude and direction of the mean force the ball exerts on the bat.

The cricket player wears padded protective equipment.

This protective equipment reduces the risk of injury to the player if they are struck by the cricket ball.

Explain how this protective equipment reduces the risk of injury to the player.

Use ideas about momentum in your answer.

Two students do an experiment to measure the speed of sound in air.

They use two blocks of wood that make a loud noise when hit together.

They do their experiment outside in a wide‑open space.

Describe how the students should use their equipment to measure the speed of sound in air.

You may draw a diagram to support your answer.

The table shows the students’ results.

Calculate the mean time for the last row in the table.

The students think that some of their time readings are anomalous.

State how the students should deal with these anomalous readings.

Explain which distance in the table is likely to give the most accurate value for the speed of sound in air.

A racing car uses an engine and an electric motor to power its wheels.

The electric motor can only operate at maximum power for part of each lap of the race.

The electric motor has a maximum power output of 1.210⁵W.

The electric motor transfers 4.010⁶J of energy when it operates at maximum power.

Calculate the amount of time the electric motor can operate at maximum power.

The diagram shows a simplified view of a direct current (d.c.) electric motor.

State what is meant by the term direct current.

Explain the purpose of the brushes and the commutator in the d.c. motor.

The electric motor in the racing car can also be used as a generator to charge a battery pack. It is known as a motor generator unit (MGU).

The rotating wheels of the car cause the magnets in the MGU to spin near a coil of wire.

This induces a current in the coil when the coil is connected to the battery pack.

Name the energy store of the battery pack that increases when the battery pack is being charged.

Explain why the kinetic energy store of the car must decrease when the MGU charges the battery pack.

This question is about nuclear fusion.

The incomplete nuclear equation shows the fusion of two isotopes of hydrogen.

Identify particle X in the nuclear equation.

Each fusion reaction releases approximately 310^–12J of energy.

Estimate how many reactions are needed to produce 1 J of energy.

Give your answer to 1 significant figure.

Explain why this fusion reaction will only happen at high temperature and high pressure.

A tokamak is an experimental nuclear fusion reactor.

Strong magnetic fields are used to contain the reactants inside the tokamak.

The diagram shows a positively charged hydrogen nucleus in a uniform magnetic field directed out of the page.

magnetic field out of page

positively charged hydrogen nucleus

The nucleus experiences a force acting to the left because of the magnetic field.

Deduce how the nucleus must behave to experience this force.

Suggest how engineers working on the tokamak could increase the force on the nucleus.

State what is meant by the astronomical term galaxy.

Which of these is a large collection of billions of galaxies?

Hydrogen is an element that can emit visible light waves.

The table shows the wavelength of one of these waves when detected from a laboratory sample of hydrogen and when detected from the hydrogen in two different galaxies.

The detected wavelengths from the galaxies are different from the detected wavelength from the laboratory sample because of the Doppler effect.

Galaxy A and galaxy B are both moving relative to Earth.

Compare the motions of galaxy A and galaxy B relative to Earth.

Use data from the table to calculate the speed of galaxy B relative to Earth.

[speed of light, c = 3.010⁸m/s]

A student investigates the rate of cooling of water in a beaker.

The student pours boiling water into a beaker and monitors the temperature of the water for a period of time.

The graph shows the student’s results.

The rate of cooling is represented by the gradient of the graph and is measured in C/s.

By drawing a tangent to the curve, determine the rate of cooling of the water at 70C.

The student repeats the investigation with the same beaker wrapped in woollen insulation.

Sketch another line on the graph to show the expected results when the beaker is wrapped in woollen insulation.

Assume that the starting temperature of the water is 82C.

Diagram 1 shows a machine used for demonstrating electrostatics.

When the handle is turned, the dome becomes positively charged.

In terms of electron movement, give a reason why the metal dome becomes positively charged.

When the handle is turned for 15 s the dome gains 0.50 J of energy in its electrostatic store as it becomes charged.

The voltage between the dome and the earth is 120 kV.

Calculate the mean charging current during this time.

The metal dome is discharged.

A thin metal case is then placed on top of the metal dome, as shown in Diagram 2.

When the handle is turned, the thin metal case moves upwards away from the dome.

Explain why the thin metal case starts to move upwards.

Explain why the metal case reaches a maximum height above the metal dome.