Physics

# Define Thermal Capacity and Specific Heat

Thermal Capacity

The amount of heat required to raise the temperature of a body through 1K is called the heat capacity of that body. The heat capacity depends on the material and the mass of the body. Its unit is JK-1. The heat capacity of a body is 10 JK-1 means 10 J heat is required to raise the temperature of the body through 1K.

Let, Q amount heat is required to increase the temperature of a body through Δθ.

Therefore the amount of heat required to raise tilde temperature of the body through 1K is Q/ Δθ Heat capacity, C = Q / Δθ

Specific Heat

The amount of heat required to raise the temperature of a body of mass 1Kg through 1K is called the specific heat of the material of that body. It is denoted by the letter S.

Mathematically we can express,

Specific heat, S = C/m = 1/m * Q / Δθ = Q / mΔθ

Unit: The unit of specific heat is Jkg-1 K-1. The specific heat of lead is 130Jkg-1K1 means 130J heat is required to raise the temperature of 1kg of lead through 1K.