Beach Physics
(Sfx: beach/ocean ambience)

     SUMMER HAS COME AND FAMILIES EVERYWHERE ARE HEADING TO THE BEACH  

(sfx: series of door slamming mother clalling to kids "don't forget to bring the sun tan
lotion," kids running and mother" watch out the sand is. . ." "Yeow!" "hot")   

FAMILIES ARE ALSO PROBABLY SCORCHING THEIR FEET ON THE HOT SAND.  WHY DOES THE
SAND GET SO HOT?  AFTER ALL IT'S WHITE AND IT'S USUALLY DARK THINGS THAT STORE UP
HEAT.  YOU'D THINK GRASS WOULD GET HOT AND SAND WOULD STAY COOL.   PHYSICIST
DAVID HAASE AT NORTH CAROLINA STATE UNIVERSITY EXPLAINS HOW COLORS ARE
LINKED TO HEAT.

     Haase: "All materials absorb different amounts of different wavelengths of
radiaton and the light that they don't absorb they reflect and that's the colors you see.
For instance, green grass is green because it abosrbs all the colors of light except green
light and it reflects that into your eyes and that's what you see"

     THINGS THAT ARE BLACK ABSORB ALL THE LIGHT AND THEREFORE HEAT.  THINGS
THAT ARE WHITE ARE SENDING ALL THE LIGHT BACK TO YOUR EYE AND SO THEY USUALLY
STAY COOL--BUT NOT SAND.

     Haase: "it's sort of strange that white sand is a material that does not absorb very
much visible light, . . . but it abosrbs very heavily in the infrared region of light, so it tends
to gather a lot of heat form the sun and it becomes very hot."

     ANOTHER REASON WHY SAND IS SO MUCH HOTTER THAN GRASS IS THAT SAND
STORES UP THAT HEAT WHILE GRASS DOESN'T.

     Haase: "well the sand and the grass both get rid of heat by giving up their heat to
the air . . . the sand is very closely packed and the air doesn't have a whole lot of surface
to go around it, so the air can't give up its heat very easily, but the blades of grass sit up
and they wave in the breeze and they can get rid of their heat."