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)
To calculate the energy required for sweating and evaporation of 1kg of water from your skin, we can use the formula:
Energy = mass x latent heat of vaporization
a) Sweating and evaporation of 1kg of water from your skin:
The specific latent heat of vaporization of water is given as 2.3 MJ/kg.
Energy = 1kg x 2.3 MJ/kg
Energy = 2.3 MJ
Therefore, your body would need approximately 2.3 megajoules (MJ) of energy for sweating and evaporation of 1kg of water from your skin.
b) Heat loss by radiation at the rate of 100 watts for 12 hours:
To calculate the energy required for heat loss by radiation, we can use the formula:
Energy = power x time
Energy = 100 watts x (12 hours x 3600 seconds/hour)
Energy = 100 watts x 43,200 seconds
Energy = 4,320,000 joules
Therefore, your body would need approximately 4,320,000 joules (or 4.32 megajoules) of energy for heat loss by radiation at the rate of 100 watts for 12 hours.
Please note that these calculations provide an estimate for the amount of energy needed and may vary depending on individual conditions and circumstances.