Four modes of energy transfer

1. The Hot sun (radiative exchange)
-The heat content of a substance is proportional to the random kinetic energy of its molecules.
-Temperature is a measure of the average random kinetic energy of the moleculers in a substance.

2. The Cold floor tile (conduction)
-If 2 substances at different temperatures are in contact with others. Heat is transferred from the high-temperature substance to the low by conduction.
-Conduction = a direct molecular interaction.

3. The "chilling" wind (convection)-Convection = heat transport by a moving fluid. following the similar rule as the mass/momentum transport. ex) The force of wind or water on an organism is a manifestation of the transport of momentum.

4. The "stifling" humidity (reduced latent heat loss)
-To change from a liquid to a gaseous state at 20" C, water must absorb about 2450 joules per gram (the latent heat of vaporization), almost 600 times the energy required to raise the temperature of one gram of water by one degree. Evaporation of water from an organism, which involves the latent heat required to convert the liquid water to vapor and convection of this vapor away from the organism, can therefore be a very effective mode of energy transfer. Almost everyone has had the experience of stepping out of a swimming pool on a hot day and feeling quite cold until the water dries from their skin.

-An introduction to environmental biophysics, Gaylon S.Campbell, John M Norman