Energy Sources (CIE IGCSE Physics)

Energy sources used to generate electricity are shown in the box.

Which energy sources are non-renewable?

Draw a ring around each energy source that is non-renewable.

The diagram shows a geothermal power station.

Describe how the geothermal power station generates electricity.

In America, it is estimated that tidal power costs $150 per MWh, whereas coal costs $60 per MWh. This is partly due to construction costs of the turbines for tidal power. 

Suggest why it is expensive to construct tidal turbines. 

Fusion is occurring in the centre of a star. The region in which a certain type of fusion is occurring has a diameter of 150 000 km.

Calculate the surface area of this sphere. 

The weight of the star around the core exerts a large force on the core. 

The core experiences a pressure of 26.5 × 10¹⁵ Pa.

Extended

Compare the advantages and disadvantages of nuclear fusion and nuclear fission.

Calculate the number of joules in 1 GWh.

Extended

Tidal power electrically transfers energy in the kinetic store of moving water. 

When the tide is moving, a portion of sea water passes through the turbine. The turbine has a cylindrical shape as the turbine spins in a circular path. A turbine is shown in Fig. 1.1.

The cylinder is 24 m long and has a radius of 5.0 m. The tide is travelling at 6.0 m/s.

In America, it is estimated that tidal power would cost $150 per MWh produced, whereas coal only costs $60 per MWh produced. 

Suggest why tidal power is more expensive than power from fossil fuels.

Some ocean environmental groups oppose the use of tidal power, stating that it can physically harm aquatic life, as well as impacting their ability to communicate. 

Suggest why these statements could be correct.

A coal power station has an average output of 400 MW. Explain how, in a power station, burning a fuel causes a generator to produce an alternating current.

Extended

The Sun has a total power output of 3.8 × 10²⁶ W across its whole surface. The surface of the Earth receives 5.0 × 10⁻⁸ % of this power. 

Calculate the total power the surface of the Earth receives from the Sun.

Extended

The power that the Earth receives from the Sun is actually twice the percentage given in part (b).

Extended

Fig. 5.1 shows a wind turbine.

Describe how the wind turbine produces electricity.

Wind turbines are used in many countries to replace coal-fired power stations.

A tidal barrage (dam) produces electricity using tides. Fig. 5.1 shows a diagram of a tidal barrage (simplified).

The water behind the barrage (dam) has most of its energy in one of its energy stores. State the name of this energy store.

Explain how the tidal barrage (dam) produces electricity.

Fig. 5.1 shows a geothermal power station. It generates electricity.

In a geothermal power station, the process of generating electricity includes seven stages.

Four of the stages are shown below.

The flow chart in Fig. 5.2 shows the seven stages, but it is incomplete. Complete the flow chart by adding the letters P, Q, R and S in the correct sequence.

The cost of electricity obtained from a geothermal power station is similar to the cost of electricity obtained from wind turbines.

 
Describe one advantage and one disadvantage of using a geothermal power station to generate electricity compared with using wind turbines.

Nuclear fission is used in nuclear power stations to release energy.

Describe how the energy is used to generate electricity.

Describe two environmental problems that arise from using nuclear power stations.