7B35.50 - Paddle Wheel Tube

Hook the induction coil to the electrodes of the tube, turn on and adjust the power and the direction of the current of the coil. The Crookes tubes are designed to be evacuated during the above operation so that different patterns and characteristics may be observed.
Changing the direction of the current in the induction coil will change the direction that the paddle will move.
The older of the two tubes has very nice fluorescent spots that appear on the paddle wheel when running.
Code Number:
7B35.50
Demo Title:
Paddle Wheel Tube
Condition:
Good
Principle:
Electron Beams and Properties
Area of Study:
Modern Astronomy
Equipment:
Induction Coil, Paddle Wheel Tube.
Procedure:

Hook the induction coil to the electrodes of the tube, turn on and adjust the power and the direction of the current of the coil.  Changing the direction of the current in the induction coil will change the direction that the paddle will move.  The older of the two tubes has very nice fluorescent spots that appear on the paddle wheel when running.

References:
  • T. E. Humphrey, Vaishnavi Calisa, "A Century-Old Question: Does a Crookes Paddle Wheel Cathode Ray Rube Demonstrate that Electrons Carry Momentum?", TPT, Vol. 52, # 3, March 2014, p. 142.

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