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?
(a) The device P is Compact Fluorescent Lamp or CFL and device Q is Filament type bulb. CFL consumes less number of electricity units.
(b) The component which is present in filament type bulb but not in CFL is filament.
(c) Filament type bulb wastes electricity by radiating a lot of heat energy.
(d) P i.e. CFL is more efficient than filament type bulb.
(e) If all of us switch to devices like CFL, coal is most likely to be conserved. Coal is used for generating electricity.