Heat | Heat Energy

 

Heat | Heat Energy :- Heat is a form of energy that is being transferred from one body to another or between adjacent parts of a body as a result of temperature difference.

When a body is heated, its temperature increases and molecules begin to move with greater kinetic energy.

The word “heat” is meaningful only as long as the energy is in transit(due to temperature differences), once it is transferred, it becomes the internal energy of the receiving body. In this manner, articulations like “heat in a body” or “heat of a body” are absurd.

Unit of Heat

S.I. Unit :- Joule (J)

Definition : One joule is defined as the amount of work done when a force of one newton acts on an object in the direction of its motion through a distance of one meter.

∴ 1 J = 1 N × 1 m = 1 Nm

C.G.S Unit :- calorie(cal.)

Definition : The amount of heat needed to increase the temperature of 1 gm of water from 14.5 ºC to 15.5 ºC (since there is a slight temperature dependence) at one atmospheric pressure is called 1 calorie.

1 calorie = 4.18 joules