Heat transfer MCQ with Answers

1)Conduction: Conduction is a process of heat transfer from one particle of the body to another in the direction of fall of temperature. The particles themselves remain in fixed position relative to each other. The heat transfer in a metal rod is by conduction.

2)Convection: Convection is a process of heat transfer from one particle of the body to another by convection current. In this case, the particles of the body move relative to each other. The heat transfer, in case of liquids and gases, takes place according to convection.

3)Radiation: Radiation is a process of heat transfer from a hot body to a cold body, in a straight line, without affecting the intervening medium. The heat of sun reaches to us according to radiation.

Metals are particularly good conductors of heat because their particles are very closely packed so the vibrations are passed on very quickly. They also contain large numbers of free electrons. These drift slowly through the structure, giving metals their strength and other properties. As the metal is heated, the free electrons closest to the heat source are heated.

This makes them move faster and they travel through the metal, colliding with both atoms and other electrons. This naturally makes these vibrate faster (or move through the metal faster in the case of collisions with other free electrons). Thus, the heat is passed quickly through the metal.