A 61.8-kg runner produces 279 J of energy per second while running a marathon. Assuming 11.3% of the energy is delivered to the muscle tissue and that the excess energy is removed from the body by evaporation of sweat, determine the mass of bodily fluid (assume it is water) lost per hour.

The mass of bodily fluid lost per hour is 0.369 kg

Explanation:

Mass of runner kg

Energy produced by the body J

Here 11.3% of energy is delivered to the muscle tissue, that implies 88.7% of this energy used to evaporate the sweat as heat.

Heat energy used in one hour is

From the formula of latent heat,

Where      ( Latent heat of vaporization for water )

    kg

Therefore, the mass of bodily fluid lost per hour is 0.369 kg

a.   mass number from atomic number