To cause condensation to occur you must cool the air to its dew point temperature.  Dew forms in the morning when the ground or objects on the ground (like an automobile) cool and become colder than the air above.  When moist air comes into contact with the cold ground, the air cools and condensation may occur.  Your glasses or sunglasses steam up when you leave a cold air conditioned room in the summer and step outside into warm humid air.  Water vapor condenses when the moist air comes into contact with your cold sunglasses.  During condensation heat is released into the surroundings.


Winds spiral into surface centers of low pressure.  This is convergence.  Warm and cold fronts also cause air to rise.


Blowing on a bowl of soup is convection.  Hot soup will evaporate.  Evaporation takes energy from the soup and causes it to cool.  This would be latent het energy transport.




Our perception of cold is a measure of how much rapidly our body is losing energy.  Rate of energy loss by conduction depends on the thermal conducitivity of the material and also on the temperature gradient or temperature difference.  There is a larger temperature difference between your body and 50 F water than there is between your body and 70 F water.  The 50 F water will feel colder.

This is the same kind of situation as in Question 8.  There is an even larger temperature difference between your hand and a block of ice.  This is what causes the rapid loss of energy and the feeling of cold.


The first thing to realize in this question is the energy lost by the water when it cools is the same energy gained by the aluminum as it warms. 

Then this is similar to a problem we did in class.  In that case we added equal amounts of energy to equal masses of water and soil and calculated how much of a temperature change there would be for each.  The soil had a larger temperature change than the water because the soil had lower specific heat.

Here the aluminum undergoes a larger temperature change which must be because it has lower specific heat than the water.


Because water is involved you might conclude this was an example of latent heat energy transport.  But there is no mention of water evaporating or water freezing, just organized motion of water.  This is therefore energy transport by convection.

In Question 13 the air on the right side is sinking because it has come into contact with cold window glass and cooled.  This increases the density of the air and causes it to sinks.  It warms and begins to rise when it comes into contact with the other window pane.