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Question
Heat and work are equivalent. This means, ____________ .
Options
when we supply heat to a body we do work on it
when we do work on a body we supply heat to it
the temperature of a body can be increased by doing work on it
a body kept at rest may be set into motion along a line by supplying heat to it
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Solution
the temperature of a body can be increased by doing work on it
According to the statement "heat and work are equivalent", heat supplied to the body increases its temperature. Similarly, work done on the body also increases its temperature.
For example: If work is done on rubbing the hands against each other, the temperature of the hands increases. So, we can say that heat and work are equivalent.
When heat is supplied to a body, we do not do work on it. When we are doing work on a body, it does not mean we are supplying heat to the body. Also, a body at rest cannot be set in motion along a line by supplying heat to it. So, these statements do not justify the equivalence of heat and work.
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