Difference between heat and work.

1.	Difference between heat and work.
Answer» (i) Heat is a mode of energy transfer due to temperature difference between the system and the surroundings. Work is the mode of energy transfer brought about by means that do not involve temperature difference such as moving the piston of a cylinder containing the gas, by raising or lowering the weight connected to it. (ii) When heat is supplied to a gas, its molecules move faster in all directions at random. So heat is a mode of energy transfer that produces random motion, when a piston compresses a gas to do work on it, it forces the molecules to move in the direction of piston’s motion. So work may be regarded as the mode of energy transfer that produces organised motion.

Answer»

(i) Heat is a mode of energy transfer due to temperature difference between the system and the surroundings. Work is the mode of energy transfer brought about by means that do not involve temperature difference such as moving the piston of a cylinder containing the gas, by raising or lowering the weight connected to it.

(ii) When heat is supplied to a gas, its molecules move faster in all directions at random. So heat is a mode of energy transfer that produces random motion, when a piston compresses a gas to do work on it, it forces the molecules to move in the direction of piston’s motion. So work may be regarded as the mode of energy transfer that produces organised motion.

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