A person buys two electrical devices P and Q for lighting purposes in his house. The device P consumes only 5 units of electricity in a month but device Q consumes 15 units of electricity in a month when used for the same number of hours daily. The device Q wastes a lot of electricity by radiating energy C but P does not do so.
(a) What type of device is (i) P, and (ii) Q ?
(b) Name one component which is present in Q but not in P.
(c) Name the energy C.
(d) Which device is more energy efficient : P or Q ?
(e) Which fossil fuel is most likely to be conserved if all of us switch over to devices like P ?

Answer

(a) (i) Compact Fluorescent Lamp (CFL) (ii) Filament type bulb (or lamp) (b) Filament (c ) Heat energy (d) P (e) Coal