Question

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 1

Heating of a car kept in sunlight:

1. Infra-red radiations in sunlight pass through the glass and heat the interior of the car.
2. The radiation emitted by upholstery and other inner parts of the car cannot pass out of the glass, so the heat trapped inside raises the temperature of the interior.
3. This is because glass is transparent to infrared radiation from the sun and has a smaller wavelength than that emitted by the interior of the car, which is of a longer wavelength to which the glass is opaque.