Sunday, February 25, 2007

Cheap Tech Tool: Non-Contact Thermometer

I recently purchased a non-contact thermometer from Harbor Freight Tools. I think I may be buying a few more. You just point it at a surface, push a button and a second later you have your temperature reading. In a matter of seconds you can compare the temperature of a window, window pane, and the wall surrounding the window. Or you can look at the temperature of the floor by an outside door and how it varies with distance from the door.

The one I've been playing with currently is running for $6.99 (I bought mine for $9.99). It has a temp range of -33 to 110 degrees C (-27 to 230 Deg.F) so is a little limited and I haven't been able to gauge it's precision yet. Its ease of use and price make up for any of it's shortcomings, however.

Possible Labs or Demos:
  • Black absorbs heat more quickly, does it radiate more heat than white?
  • Insulators and conductors - Both may be the same temperature, but do they feel the same when you touch them? A piece of Styrofoam and metal fresh from the fridge or freezer would do nicely.
  • You can replace melting wax on the ends of conductors with a quantifiable temperature.
  • Resistors in a circuit, which ones get the hottest? Why?
You can get much more expensive non-contact thermometers that have wider temperature ranges and use lasers to show the exact spot the reading is coming from, but I have yet to find a cheaper one.


Anonymous said...

Thanks for the info on the non-contact thermometers. There are companies out there that sell temp probes, etc (PASCO) directly connected to one's computer as well.

However, Texas has kids still reading bulb thermometers on the state assessment test! At least reading a customary thermometer is good practice for using number lines.


Steve said...

I've used the Vernier version of the computer/calculator based temperature probes in the past and they are cool.

I really like the non-contact thermometer because it gives a darn near instantaneous reading. As a bonus it's much cheaper than the computer thermometers as well.