Q.1.
What is the efficiency of a solar cell if 1000 J of solar energy hits the cell and 200 J are converted into electrical energy?
Q.2.
What is electrical energy converted into when a drill is used?
Q.3.
An old boiler system is replaced with a solar heating system. The old boiler cost £250 per year to run. The new solar heating system costs £0 to run but cost £2,000 to install. How long will it take to start saving money?
Q.4.
Electrical energy in a kettle changes to what type(s) of energy?
Q.5.
Electrical energy in a TV changes to what type(s) of energy?
Q.6.
An energy saving bulb replaces a 60 W lamp which cost £4.65 each year to run and 20p to buy. The new low energy bulb costs just £2 per year to run and 65p to buy. How long will it take to start saving money on the running costs due to the change?
Q.7.
What would be a good idea to save energy and money?
Q.8.
How could you save money boiling a kettle for one cup of tea?
Q.9.
Which appliance uses the most energy?
Q.10.
A heat exchanger can be used to convert which type of wasted energy into a useful source of power?