Define thermal capacity and water equivalent of a body. State their units and how are they related ?

Explanation

Thermal capacity of a body is defind as the amount of heat required to raise the temperature of the whole body through `1^@C` or `1K.` Quantitatively, thermal capacity `=("heat given "(Delta Q))/("rise in temp "(Delta theta)) = (ms Delta theta)/(Delta theta) = mxxs` Where m is the mass and s is the specific heat. Unit of thermal capacity is cal `K^(-1) or JK^(-1).` Water equivalent of a body is defined as the mass of water in gram which would absord or evolve the same amount of heat as is done by the body in rising or falling through the same range of temperature. If `Delta Q` amount of heat is given to raise the temperature of w amount of water through temperature `Delta theta` then `Delta Q= w Delta theta or w = Delta q// Delta theta` The unit of water equivalent is gram . Quantitatively, thermal capacity of a body is equal to its water equivalent.