a) Multiply your heat of vaporization number by 1 kg.
That is the answer in Megajoules.
Multiply by 1 million for joules
b) 12 hours is 43,200 seconds.
Multiply that by 100 joules/s for the answer in joules
How much energy would your body need to provide for the following :
a)sweating and evaporation of 1kg of water from your skin.
b)heat loss by radiation at the rate of 100 wats for 12 hours.
(the specific latent heat of vaporisation of water is 2.3MJkg-1)
2 answers
2.3 Million Joules is 550 kcal or 550 "food Calories"
Fortunately, we burn a lot of Calories doing nothing
Fortunately, we burn a lot of Calories doing nothing