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MOTIVE POWER OF HEAT.
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corresponding to the temperature t, is known. For, by § 30, equation (6), we have
where dq is the quantity of heat absorbed, when the volume is allowed to increase from v to v + dv; or the quantity evolved by the reverse operation. Hence we deduce
(8) |
Now, is constant, since the temperature remains unchanged; and therefore we may at once integrate the second number. By taking it between the limits V' and V, we thus find[1]
(9) |
where Q denotes the required amount of heat evolved by the compression from V to P'. This expression may be modified by employing the equations PV = P'V' = p0v0 (1 + Et); and we thus obtain
(10) |
- ↑ The Napierian logarithm of is here understood.