College Physics (4th Edition)

The rate of heat lost through transpiration is $23.3~W$
We can find the heat required to evaporate 618 mg of water: $Q = m~V$ $Q = (0.618~g)(2260~J/g)$ $Q = 1396.7~J$ We can find the rate of heat lost through transpiration: $P = \frac{Q}{t} = \frac{1396.7~J}{60~s} = 23.3~W$ The rate of heat lost through transpiration is $23.3~W$