Which radiations of sunlight are used in heating a solar cooker?
ultra violet radiation
infra red radiation
visible light
all of the above
Infra red radiations from the sun are used to heat the solar cooker.
Which of the following are used in electric water filters to kill all the harmful micro-organisms present in tap water and make it absolutely safe for drinking?
(a) infrared radiation
(b) gamma radiation
(c) visible radiation
(d) ultraviolet radiation