Practice Paper 2 (Edexcel IGCSE Physics)

The diagram shows part of an electric circuit.

Complete the circuit diagram by adding:

• a resistor in series with the lamp and battery

  • a second lamp in parallel with the first lamp
  • a voltmeter that measures the voltage across the resistor
  • an ammeter that measures the current in the resistor

The current in a resistor is measured for different voltages.

The table shows the results.

(i) Plot a graph of this data on the grid.

(ii) Circle the anomalous point on the graph.

(iii) Draw a line of best fit.

(i) State the equation linking voltage current and resistance.

(ii) Use your graph to find a value for the resistance of the resistor.

resistance = ............................................... Ω

An electric vehicle has a rechargeable battery.

The battery is recharged by connecting it to a charging station.

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The battery voltage is 385 V.

(i) State the amount of energy transferred when one coulomb of charge passes through a potential difference of 385 V.

energy transferred = ............................. J

(ii) Show that, when a charge of 180 000 C passes through the battery, the total amount of energy transferred to the battery is about 70 MJ.

(iii) During the charging process, energy is also transferred to the charging station from the mains supply.

Explain why the amount of energy transferred from the mains supply is more than 70 MJ.

Charging takes 110 minutes and causes a total charge of 180 000 C to pass through the battery.

(i) State the equation linking charge, current and time.

(ii) Calculate the average charging current in the battery.

current = ........................ A

An electric kettle is connected to the 230 V mains supply. The power of the kettle is 960 W.

(i) State the equation linking power, current and voltage.

(ii) Show that the current in the kettle is about 4 A.

The 960 W kettle is earthed and fitted with a fuse.

Explain how this can protect the person using the kettle if there is a fault.

A student has a pack of fuses labelled 2 A.

Explain how she could use one of these fuses to check that the label is correct.

A student investigating static electricity charges two balloons and hangs them side by side. They observe the balloons do not hang vertically, as shown in the diagram.

Explain why the cotton threads are not vertical.

The student charges the balloon by rubbing it with a cloth. The balloon becomes negatively charged.

(i) Explain how the balloon becomes negatively charged.

(ii) Compare the charge on the cloth compared to the balloon before and after rubbing the balloon.

The student investigates the effect of putting charged balloons on different surfaces. They put one charged balloon against a metal cabinet and one charged balloon against a wall.

(i) Describe what happens to the charge on the balloon when it touches the metal cabinet.

(ii) The student charges another balloon and holds it against a wall. The charged balloon sticks to the wall when he lets go.

Suggest why the balloon sticks to the wall.

A student feels cold at night and decides to sleep under a thick woollen blanket.

Explain how the woollen blanket helps to keep the student warm.

The student says

Do you agree with the student? Explain why.

The photograph shows a small aeroplane, of mass 600 kg.

This aeroplane has an electric motor powered by fuel cells. Fuel cells use hydrogen gas and provide an electric current.

The velocity of the aeroplane is 28 m/s.

(i) State the equation linking kinetic energy, mass and velocity.

(ii) Calculate the kinetic energy of the aeroplane.

Kinetic energy = ......................... J

The aeroplane takes off and climbs to a height of 1000 m.

(i) State the equation linking gravitational potential energy (GPE), mass, g and height.

(ii) Calculate the gravitational potential energy gained by the aeroplane.

(iii) The fuel cells provide a maximum total power of 24 kW. The aeroplane also carries a large rechargeable battery.

Show, by calculation, that the aeroplane needs this extra source of power to climb to 1000 m in 3 minutes.

(iv) The aeroplane uses fuel cells connected together in series in a ‘stack’. The voltage of each fuel cell is 0.6 V. The maximum current in each fuel cell is 30 A. Show that there must be more than 1300 fuel cells in the stack.

Which of the following is a scalar quantity?

State what is meant by a moment of a force.

A uniform seesaw is in equilibrium with a box placed on each side.

The box on the left has an anticlockwise moment of 150 N m about the pivot.

The box on the right has weight W.

(i) State the principle of moments.

(ii) State the clockwise moment due to the box on the right.

Show that the weight W of the box on the right side of the seesaw is 100 N.

The box on the left-hand side of the seesaw is now removed.

State and explain what happens to the seesaw.

The photograph shows a hammer just before it hits a nail.

The mass of the hammer is 0.50 kg. When it hits the nail, the hammer is travelling downwards with a velocity of 3.1 m/s.

(i) State the relationship between momentum, mass and velocity.

(ii) Calculate the momentum of the hammer.

momentum = ............................... kg m/s

(iii) The hammer stops quickly when it hits the nail.

The momentum of the hammer reduces to zero in 0.070 s.

Calculate the amount of force that causes this to happen.

force = ........................................ N

As it enters the wood, the nail exerts a force on the wood. At the same time, the wood exerts a force on the nail.

Explain how these two forces are related.

Both ends of the nail exert pressure when the nail goes into the wood.

Explain why the nail exerts more pressure on the wood than it does on the hammer.

This question is about determining the specific heat capacity of aluminium.

A block of aluminium has a mass of 0.32 kg and an initial temperature of 30 °C. The block is heated until it has a temperature of 75 °C. This takes 2.5 minutes.

What is the average thermal power transferred away from the metal block?

You may take the specific heat capacity of aluminium to be 900 J kg⁻¹ K⁻¹.

A student wants to determine the specific heat capacity of aluminium. They use the apparatus shown in the diagram.

A piece of string is tied to the aluminium block so it can be transferred from the boiling water to the cold water.

Describe how this apparatus could be used to determine the specific heat capacity of aluminium.

Your answer should include:

• any additional pieces of equipment required

  • how to obtain the necessary measurements
  • how the measurements should be used to calculate the specific heat capacity of aluminium