Let us suppose a body of mass m is heated to increase its temperature from t1 °C to t2 °C by supplying heat Q
Heat gained or lost by a body is directly proportional to the mass of the body and change in temperature.
i,e Q ∝ m
Q ∝ dt ( dt = t2 - t1 )
combining the given two equation ,
we get,
Q ∝ mdt
or Q = smdt where s is proportionality constant and known as specific heat capacity of the substance.
Q= msdt , hence proved.