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Question
The mechanical equivalent of heat ____________ .
Options
has the same dimension as heat
has the same dimension as work
has the same dimension as energy
is dimensionless
Solution
is dimensionless
If the mechanical work done (W) produces the same temperature change as heat (H),then the mechanical equivalent of heat (J) is equal to W/H. Thus,
J = W/H
Since the unit of work and heat is the same, mechanical equivalent of heat is dimensionless.
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