question_answer 75)

  A motor car, with its glass totally closed, is parked directly under the sun. The inside temperature of the car rises very high. Explain why?

Answer:

  Sunlight emits ultraviolet radiations which pass through the 'glass and heat the car. The radiations emitted by inner parts of the cannot pass out of the glass, so the heat trapped inside raises the temperature of the interior. This is because glass is transparent to infrared raditations released from the sun, having smaller wavelength than that emitted by the interior of the car which have longer wavelength to which the glass of the car is opaque.