Question

The fastest method of heat transfer from a hot body to a cold body is-
A. Conduction
B. Convection
C. Radiation
D. None of these

Answer 1

Hint: To solve this question we have to know about all these methods, which are, conduction, convection and radiation. We know that the meaning of conduction is the development of something like warmth or power through a medium or section. We know that radiation is the emanation or transmission of energy as waves or particles through space or through a material medium.

Complete answer:
 The fastest method of heat transfer from hot body to cold body is radiation.
We know that radiation occurs at the speed of light and does not require any medium for travelling. It takes place in the form of electromagnetic waves.

This radiation incorporates: Electromagnetic radiation, like radio waves, microwaves, infrared, visible light, ultraviolet, x-beams, and gamma radiation, Particle radiation, like alpha radiation, beta radiation, proton radiation and neutron radiation, Acoustic radiation, like ultrasound, sound, and seismic waves.

We know that, Convection, measure by which warmth is moved by the development of a warmed liquid like air or water. Regular convection results from the inclination of most liquids to grow when warmed—i.e., to turn out to be less thick and to ascend because of the expanded lightness.

So, the correct answer is option C.

Note:We know that, Convection is the interaction of warmth moved by the mass development of particles inside liquids like gases and fluids. We know that Conduction shows how warmth is moved between objects in direct contact, however Convection reflects how warmth goes through fluids and gases. As against this, radiation demonstrates how warmth goes through places having no atoms.