Subject: Thermal Energy and Heat

Dear MAD

I'm currently having troubles understanding the difference
between conduction, convection, and radiation. I realize that
conduction mainly involves solids, convection is liquids and
gasses, and radiation doesn't involve any particles at all.
I've been asked the following:

1. Which of the three methods of heat transfer occur in the
following situations?
(a) Ice forms on the inside of a window.
(b) A cat stays warm by sitting on the hood of a recently
parked car.
(c) A glider soars upward as it hits some air currents.
(d) Black pipes are used for a solar energy colector.
(e) Currents gently sway above an electric radiator.
(f) You hold a cup of hot cocoa tightly to warm your hands.

I think (a) is conduction because it's a solid, (b) is also
conduction because a cat and the heat are both solids, (c)
is convection because the air currents reflect gasses, (d)
is radiation because light energy and radiant heat for solar
energy have common properties, (e) is radiation because it's
a "radiator", and (f) is conduction because the cup and your
skin are solids.

Am I thinking in the wrong manner? Is there anything which
needs to be clarified in greater detail? Please help me out!

Thank you



James Fletcher

Re:Thermal Energy and Heat