Question

“A roof accumulates solar heat during the day and radiates the heat at night” is an example of which of the following way of heat transfer?

(a) Conduction

(b) Convection

(c) Radiation

(d) Filtration

I have been asked this question during a job interview.

The doubt is from Heat Exchangers in division Building Blocks of Dairy Processing of Dairy Engineering

Answer 1

Right answer is (c) Radiation

Explanation: Radiation is the emission of heat from a body which has accumulated thermal energy. In the given example the thermal energy is converted into radiant energy, emitted from the body and absorbed by other bodies which it strikes. Almost all substances emit radiant energy.