In chemistry, the burn rate (or burning rate) is a measure of the linear combustion rate of a compound or substance such as a candle or a solid propellant. It is measured in length over time, such as "mm/second" or "inches/second". Among the variables affecting burn rate are pressure and temperature. Burn rate is an important parameter especially in the area of propellants because it determines the rate at which exhaust gases are generated from the burning propellant which in turn decides the rate of flow through the nozzle. The thrust generated in the rocket of missile depends on this rate of flow. Thus Knowing quantitatively the burning rate of a propellant, and how it changes under various conditions, is of fundamental importance in the successful design of a solid rocket motor. The con