# Another Question - Thermal Energy & Sweat this time

1. Apr 23, 2007

### miava

1. The problem statement, all variables and given/known data

If 630W is dissipated as thermal energy/heat how much liquid is lost from the body?

3. The attempt at a solution

I have got through a 3 part problem (re: energy, work etc) and found how much energy is dissipated as heat (630W), but I have no info that leads me to the answer to the last part - how much liquid is lost as sweat. I don't have information on weight, temp or anything else as it wasn't provided in the question.
The metabolic rate to 700W and the efficiency is 10% so 630W is left as heat.

2. Apr 23, 2007

### mezarashi

You'll have to make some assumptions, such as, all the heat that the body dissipates, it does so through the evaporation of sweat.

To make liquid sweat on your skin evaporate into vapor, it must under a change in phase. Something about heats of vaporization. Does this start to sound familiar with what you're doing in class?