Solved Examples & Practice Question

When the heat is absorbed by a body, its temperature increases, and when the body discharges or loses heat, its temperature falls. The heat capacity is the heat needed for raising the temperature of an object by a calculation of one degree. It can also be calculated as a ratio of the amount of heat energy that is given to the object for the resulting increase in the temperature. The expression for the heat capacity is

c=ΔQΔT�=Δ�Δ�.

Here, ΔQ is the amount of heat that is transferred, ΔT is the increase in temperature. 

There is an equal fall in temperature when the body loses the same quantity of heat. In SI units, the heat capacity can be expressed by joule per kelvin, (J/K). In the heat capacity, the body mass can have any value, which is not specified, such as unit mass etc.

An Example of the Heat Capacity

When 6400 J of heat is supplied to the body and it raises its temperature by approximately 100 degrees, then what is its heat capacity?

Solution:

ΔQ=6400J,ΔT=100∘,c=?Δ�=6400�,Δ�=100∘,�=?

Heat capacity; c

c=ΔQΔT=6400100=64J/K�=Δ�Δ�=6400100=64�/�.