Define mechanical equivalent of heat. Give its values in SI and CGS sy

1.	Define mechanical equivalent of heat. Give its values in SI and CGS system.
Answer» the mechanical equivalent of heat states that motion and heat are mutually interchangeable and that in every case, a given amount of work would generate the same amount of heat, provided the work done is totally converted to heat energy. W=JH J=W/H W is the mechanical work which is equivalent to heat energy H. Now in SI unit both work and heat are measured in Joules. So mechanical equivalent of heat J= Joule/Joule = 1 (dimensionless) In cgs units, heat is measured in calorie while work in erg. Now 1 calorie = 41800000 ergs approximately. So J= 41800000 ergs/calorie.

Define mechanical equivalent of heat. Give its values in SI and CGS system.

Answer»

the mechanical equivalent of heat states that motion and heat are mutually interchangeable and that in every case, a given amount of work would generate the same amount of heat, provided the work done is totally converted to heat energy.

W=JH

J=W/H

W is the mechanical work which is equivalent to heat energy H. Now in SI unit both work and heat are measured in Joules. So mechanical equivalent of heat J= Joule/Joule = 1 (dimensionless)

In cgs units, heat is measured in calorie while work in erg. Now 1 calorie = 41800000 ergs approximately. So J= 41800000 ergs/calorie.

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