Question

Identify the mode of transfer of heat in the following cases: 1.Placing Air conditioners near the ceiling 2.Heat transfer from one end of a spoon to another end. 3.Heat of the sun reaches the Earth._ 4.Smoke escaping from tall chimneys in factories._​

Answer 1

Answer:

1. Convection

2. Conduction

3. Radiation

4. Convection

Explanation:

1.It has to do with moving fluids like air. As air is cooled, it contracts, become denser and sink. Warmer air at the bottom is displaced and due to it being less dense, it rises

2.Heat is transferred from the hot end of the metal spoon to its cold end. A transfer of heat from the hot part of a material to its colder part (without the movement of material as a whole) is called conduction. The transfer of heat by conduction takes place within the same object.

3.It is the transfer of heat energy through space by electromagnetic radiation. Most of the electromagnetic radiation that comes to the earth from the sun is invisible.

4.Here, hot molecules of fluids move up due to lower density. The smoke coming out from the chimneys is hence an example of convection.