PURPOSE: To show that an electron beam has momentum.
DESCRIPTION: An electron tube has a paddle wheel device inside, as shown in the photograph above. When an electron beam with sufficient energy impacts the blades of the paddle wheel it will rotate the wheel and cause it to translate along the length of the tube.
The blades of the paddle wheel contain phosphor that will glow from the electron beam.
EQUIPMENT: Paddlewheel electron tube device, as photographed. Can be powered from the Electro-Technics solid state pulsating DC sparker stored in the general use cabinet.
SETUP NOTES: It must be very carefully leveled or it will not work.