Wimshurst Machine
The Wimshurst machine is an electrostatic generator based on induction (as opposed to friction). It can generate a large potential, which can be increased using a couple of Leyden Jars (capacitors). We can easily generate sparks of one or two centimeters long. The machine allow us to illustrate how mechanical energy can be readily converted into electrical energy. Furthermore, the Lynden jars allow us to demonstrate how electric energy can be stored for later release. We normally use the Wimshurst machine as a high voltage and steady current source to feed a Crook's tube. In this case, once the circuit is established, there is a beam of charged particles running down the Crook's tube. Inside this tube there is a phosphorus screen that runs along the tube, almost parallel to it. Collisions of the charged particles with a phosphorus screen generate a nice trace of the beam. We can easily see how a magnetic field alters the direction of the beam. In addition, given the polarity of the magnet, we can determine the sign of the charges in the beam. We should be able to convince the students that the particle beam is an electron beam.
| Qty. |
name |
location |
notes |
| 1 |
Wimshurst machine |
W106; North Cabinets; U1 |
|
| 1 |
Crook's tube |
W106; North Shelves; U7-L1 |
|
| 2 |
36-in black banana cable |
W104; West Wall |
|
| 2 |
36-in red banana cable. |
" |
|
| 2 |
customized large alligator clips |
stored within the tube box |
|
