Question

What are the three types of thermal energy?

Answer 1

Hint: To solve this question, we first need to know what is thermal energy. When a system or a body absorbs heat due to the motion of the subatomic particles like atoms, molecules, or ions in the system or the body, the energy gained is known as thermal energy.

Complete answer:
It can be said that the net amount of thermal energy of the system is known as heat.
Heat energy flows due to the energy difference between two substances from a substance having a higher temperature to a substance having lower energy. The internal temperature of a substance increases when there is an addition of heat.
Thermal energy is also the total internal energy of an object due to the random motion of its subatomic particles.
Now, there are three types of thermal energy or ways of transfer of heat.
1. Convection: When heat is transferred due to the actual motion of the particles, the process is known as convection. It is usually observed in gases and liquids. Upon heating, the air gets hot and carries heat energy.
2. Conduction: When heat is transferred due to the vibration of the subatomic particles in their mean positions, the process is known as conduction. Conduction is observed when the two systems are in close contact with each other. Since in solids the particles and molecules are closely packed, they are a better conductor of heat than gases and liquids.
3. Radiation: When heat is transferred from one place to another through infrared electromagnetic waves, the process is known as radiation. No medium is required for the transfer of heat using radiation. Heatwaves are radiated in all directions by hot objects at the speed of light and are either absorbed or reflected by the object it strikes.

Note:
It should be noted that the density of warm air is less than the density of cool air. This is why cool air descends below to fill the space when warm air rises above. The cool air, when warmed, again rises above. This cycle continues to produce a convection current.