GCSE Questions: Energy Sources

Q9. The diagram shows an electric road sign.

(a) The road sign is powered by an electrical generator which has an efficiency of 40%.

Complete the Sankey diagram in the grid belowfor an electrical generator which has an efficiency of 40%.

[2 marks]

(b) The road sign uses high efficiency LED bulbs. What does high efficiency mean? Tick one box.

	Tick here
the bulbs have a high energy input
a high proportion of the energy output is useful
a high proportion of the energy output is wasted

[1 mark]

In one sign the solar cells have a total power output of 200 W.

Calculate the energy that the solar cells will transfer in 1 hour.

[3 marks]

(d) Some road signs are powered by batteries recharged by both solar cells and wind turbines.

Give two advantages of having both solar cells and wind turbines available to recharge the batteries.

[2 marks]

(Total 8 marks)