Heat and Thermodynamics

3.5 Newton's Law of Cooling

In article 3.1 we have discussed nature of heat. When a body is given a certain quantity of heat, its temperature rise depends on the mass of the body and nature of the body. Amount of heat is measured by a particular unit called calorie. It is defined as the amount of heat required to raise 1 gram of water through 1°C. As this amount depends upon the initial temperature of water so a standard has been chosen, it is the amount of heat required to raise 1 gram of water from 14.5°C to 15.5°C. There are other units of heat such as British Thermal Unit, Centigrade heat unit or pound calorie, calorie is universally accepted and used. The nature of the body is manifested by another physical property called specific heat ...