Here are some things to think about as we start the unit on
"liquid crystal" thermal sensing sheets.
These questions can be
answered by simple investigations that will only take a few minutes.
There are two liquid crystal squares in your kit. They are similar
but not the same. Please note that they have a
front and a back side, and only one side does anything at all.
Inspect the "liquid crystal" thermal sensing sheets in
your kit. Touch them with your fingers and touch them
to other objects. What do they respond to? (Warning:
if the room is much cooler than 68o it's possible
nothing will happen at all. Time to bump the thermostat!).
After you have touched the thermal sensing sheet,
observe and record the sequence of colors as it returns to
room temperature.
What is the color order (from warm to cool) for the liquid crystal
thermal sensing sheet?
You may have a sample that is not black at room
temperature. View it from different angles: is the color
always the same? What do you have to do to turn it black?
Perhaps you do not have a sample that has a color
(other than black) at room temperature. What would you
have to do to the room to cause it to have a color?
Blow on the thermal sensing sheet and observe how it
responds. Are you cooling the liquid crystal,
or warming it?
As part of your discussion,
write something in your notebook about your answers to some of
these
questions -- what you decided, which questions you were sure of,
which ones don't seem to make sense.
As part of your discussion,
write something in your notebook about your answers to some of
these
questions -- what you decided, which questions you were sure of,
which ones don't seem to make sense.