Concept explainers
Whether it is possible to transform mechanical energy into heat or internal energy completely and whether the reverse may happen or not.
Answer to Problem 1Q
It is possible to transform mechanical energy into heat or internal energy completely, but the reverse may not happen.
Explanation of Solution
It is possible to convert all the mechanical energy into heat or internal energy. An example for such a case is that bringing an object moving on a surface to rest by means of friction. In such a case, the whole mechanical energy is dissipated as heat due to the friction force which oppose the motion of the object.
The complete transformation of heat into mechanical energy does not happen in the physical world. It can be assumed to happen in some ideal cases such as the adiabatic expansion of an ideal gas. According to second law of
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EBK PHYSICS FOR SCIENTISTS & ENGINEERS
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