(a) How can you visualise a power of `1 k W` ?
(b) Describe the energy changes that take place when you stop your car by using the brakes.

(a) Solar cells are used to provide the electric current to charge the batteries of a car driven by an electric motor. Describe the energy changes which take place. (b) What differences would you expect in the charging of car batteries (i) in bright sunlight (ii) on a cloudy day (iii) at night ?

How can you determine the resolving power of your eye?

If you appply some heat energy to a substance, which of the following can take place in it?

Explain how can you take care of your eyes .

Explain how can you take care of your eyes .