Unit of work in mechanics and thermo dynamics

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In mechanics, the unit of work is measured in joules, defined as the energy transferred to a mass through the product of force and distance. In thermodynamics, work is also measured in joules, leading to questions about the similarity in units despite their conceptual differences. Work is defined as a force applied over a distance, while heat refers to energy used to change a system's temperature. The first law of thermodynamics emphasizes the balance of energy, stating that work and heat must share the same units but represent different forms of energy transfer. Ultimately, work serves as a method of transferring energy rather than being a type of energy itself.
chandran
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unit of work and unit of heat

When we study dynamics,the unit of work is in joules which is the energy transferred to a mass which in turn is the product of force and the distance along which the force is applied

When we study thermodynamics, the unit of work is again in joules.

How these two can be same?
 
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Better, you say why should they be differant. What happens when an object does a work on an object? How do we measure work there?
 
Work is a kind of energy. I think that the reason to call it work is historically in the context of vapor machines. We use energy to move something that can replace men's labour such as moving a piston or something else.

The first law of thermodynamics says that the balance of energy is the rest (or the sum, depending on sign chriteria) of heat and work. It must have the same units so, but conceptually are different things. Work is a force times a displacement, energy that we use to move something. Heat is energy that we use to change the temperature of a system (for example).
 
Work is not a kind of energy. Rather it's a way of transfering energy.
 
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