4B40.66 - Radiation - Laser and Thermometer

See paragraph one in the procedure section
Code Number:
Demo Title:
Radiation - Laser and Thermometer
Radiation Heating
Area of Study:
Heat & Fluids
Digital Thermometer & bead thermocouple, alcohol thermometer, green laser pointer, sensitive thermocouple horn, green helium-neon laser if available, red helium-neon laser.

Line up the bead thermocouple and green laser on an optics bench so that the bead will be fully illuminated when the laser is turned on.  A temperature rise of several degrees C. will be observed when the laser is turned on.  A higher temperature rise will be observed if you borrow one of the high power green diode laser modules from one of the research labs. 

The sensitive thermocouple horn can be used in place of the digital thermometer.  However, you will see the temperature increase as an increase in voltage in this case. 

A regular alcohol thermometer may be used if you are using the high power green laser diode modules.  Otherwise the temperature rise will most likely be too small to see. 

Using a red helium-neon laser for this experiment will show no noticeable temperature rise.

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