8) warming your hands by a fire is an example if which heat transfer?

The heat is transferred by the process of convection.

Explanation:

There are 3 modes of heat transferred:

1. Conduction: This type of heat transfer occurs from a surface having higher temperature to a surface having lower temperature whenever there is direct contact between the two object.

2. Convection: This type of heat transfer occurs  from a surface having higher temperature to a surface having lower temperature whenever there is a movement of fluid (liquid or gas).

3. Radiation: This type of heat transfer occurs from a surface having higher temperature to a surface having lower temperature whenever there is direct transfer of energy through space.

In the question, heat is getting transferred from fire to hand. The mode of heat transfer in this process is convection because the air around the hand is getting warmed rather than our hand directly and due to the warming of air, our hand gets warmed.

Hence, the heat is being transferred by the process of convection.

the product of the pressure and volume is also constant