You 'Get It' About
Hot, Warm and Cold.
Snack: If we're going to be concentrating on contrasting temperatures, there
are no two ways about it. We HAVE to splurge and have hot-fudge sundaes today.
If you can serve low-fat frozen yogurt or ice milk, that would save on the fat
and calories of ice cream. But as long as you keep your sundae to one or two
dips, it won't be so bad. You also can find sugar-free and/or low-fat fudge
sauce, believe it or not, in the diet aisle. Put a glass jar of it in the
microwave and heat for one minute on high. Be SURE to take the metal lid off
first - duh! Just kidding. Stir after a minute, and if it's still cool or just
warm, put it in for another minute on high. Stir again. When it's pretty darned
hot, glob a nice big glob on top of your froyo or ice milk. The best part of
all is watching the fudge sl-o-o-o-owly dribble down the scoop. Oh, yeah!
Quick access to a microwave oven
Blindfold (if more than one person is present)
You know about our friends, the molecules.
They're the tiny little conglomerations of even tinier little atoms. Well,
there are tons and tons and TONS of molecules right in your chubby little
fingers. You can't even COUNT them, there are so many! Bet you didn't know you
had soooo many little bitty parts of yourself.
Aha! I just saw one MOVE! AAAIIIIEEE!!!!
Just kidding. Ahem. Just a little science
Anyway, the point is, yes, molecules really
DO move. They're moving all the time. Obviously, they're so eentsy weentsy, you
can't even see them, much less see them move - even if you squint really,
There's that nerdy science humor again.
ANYway . . . there are
molecules in the tissues of your fingertips that can vibrate, or move,
thousands of times per second. Imagine that! Try wiggling your finger for one
second. Did you maybe move it five or six times? Well, big whoop - compared to
But the thing is, the
warmer these molecules get, the faster they vibrate. That's how we can come up
with the temperature of an object: we measure the average motion, or "kinetic"
(meaning movement) energy, of the object's molecules.
You also have to keep in
mind that these measurements of heat are all relative. You can actually "trick"
your senses based on the environment in which you are measuring, based on
what's going on with your molecules.
Let's demonstrate this:
If you're by yourself, do
this activity by yourself, but repeat it later with somebody else and blindfold
them to take them through the activity and see the big surprise.
ANYway . . . fill the
three cups with tap water, only put one in the microwave and get it quite warm,
though not too hot to the touch. Try 30 seconds on high, but if that's too hot
to stick your finger in the water comfortably, let it cool off 'til you can. Make
the second one at room temperature of water. And fill the third one with cold
water, with a couple of ice cubes added for good measure. You should end up
with warm-almost-hot, room temp, and ice-cold cups of water.
Put them in front of you
in that order - warm, regular, cold.
Now put your left index
finger (your "pointer" finger) in the warm water and your right index finger in
the cold water. Count to 20, slowly.
As soon as you're done,
quickly dip both fingers into the room temperature water in the middle of the
Notice what your fingers
are "telling" you:
Your left index finger
will feel like it is submerged in cool water, while your right index finger
will "think" it's in warm water.
Yet they're in the same
darned container with the same darned temperature!
When you do this to
someone blindfolded, ask them at the end if their two fingers are in two
different containers, or the same one. Most times, they'll INSIST they're in
two different containers! You will laugh like crazy, and they will be mad,
frustrated and protesting. Enjoy!
Those fingers are
confused! They belong in a Digital Loony Bin. (Get it? Fingers are, after all,
"digits"? Sigh. Sorry, again.)
Anyway . . .
How come this happens? Well, it goes back to
our crazy, dancing molecules. When the left finger was in the hot-warm water,
it absorbed some of the heat, which made those skin molecules vibrate like
crazy. Then when you put it into the regular-temperature water, some of that
heat was transferred out of the finger, into the water. The finger which a
second ago felt pretty warm suddenly feels cool because the vibrational energy of
its molecules has slowed down quickly.
Similarly, when the other
finger was plunged in the ice-cold water for 20 seconds, molecular action was
slowed down because of the cold. Then when that cold finger was shifted into
the regular-temperature water, it quickly absorbed some of the heat-energy from
it, and felt warmer as a result.
Hot-warm-cold molecules in
your fingers. Cool! Do you give that a . . . THUMBS UP?