Materials
cardboard
foil-and-paper candy wrapper
pencil
spool
tape
A solid thermometer
Most thermometers you’ve seen probably use a liquid to measure
temperature. But solids can be used to measure heat, too. Solids expand
and contract as they get warmer and cooler, just as liquids do. Here’s a
simple thermometer that measures heat with solids.
Press the candy wrapper as flat as you can. On the paper side, draw a
pointer the size of the one shown here. Cut out the pointer.
Tape the straight end of the pointer to the spool. Place the spool on
the cardboard, close to one edge. Aim the pointer at the middle of the
cardboard. Then tape the spool down. Your thermometer is ready to use.
Take your thermometer to a very cool place and leave it there for a few
minutes. Which way does the pointer bend? Make a mark under the pointer
and print C by it. This is the \”cold” end of youi’ temperature scale.
Next leave the thermometer in a very warm spot. Which way does the
pointer bend
this time? Make a mark under it and print H for the \”hot” end of the
temperature scale.
Your thermometer works because the metal side of the pointer expands and
contracts more than the paper side. In a cold place, it gets shorter
than the paper side and pulls the pointer one way. But in a hot place,
it gets longer than the paper side and pushes the pointer the other way.
Can you find places with temperatures between C and H? The direction
and distance the pointer bends will show you about how warm or how cool
each place is.
