6B40.15 - Wavelength of Light vs Temperature
To demonstrate that the temperature will vary when the thermoprobe is illuminated with red light and near IR vs. blue light and soft UV.
Using the old-time slide projector, connect it to an on/off switch. Place the mounted prism onto the large wooden block. Pull out the thermocouple with the . Project the dispersed light onto a blocking plate and place the thermoprobe against the plate in the beam of one of the colors. Project the temperature probe using a camera. Move the thermoprobe around to make sure the temperature values change as you move it from Red to Blue light.
Turn on the projector and shine it through the prism to produce a dispersed pattern onto the image plate. Move the thermoprobe in front of either the red or blue light. Have the class observe the temperature. Then move the thermoprobe to the other side of the dispersed pattern and observe the change in the temperature. You can also show that beyond the red light, there is infrared and beyond the blue light, there is UV. A temperature will still show up even though we cannot physically see the presence of that radiation.
Shorter wavelength light has a higher energy than longer wavelength light, therefore producing a higher temperature reading for shorter wavelengths. You can also show the presence of UV and IR light that is beyond what our eyes can see. A temperature reading still is possible even though the light is not resolved by our eyes.