PIRA 5B20.15 Gauss's Law: Faraday Ice Pail with an Electroscope
Photo Shows the Demonstration Apparatus Used by the University
of Texas at Austin
Set Up Instructions / Notes:
- This demonstration includes a Wimshurst machine, two discharge spheres and a couple of electroscopes.
- A metal pail is attached to the top of one electroscope.
- The demonstration only works in a very low humidity environment - a condition which is not usually achievable in Pai 4.42. -
***** Demo Procedure is as follows: *****
- Charge one of proofing spheres by touching it to one of the ball end electrodes of the Wimshurt machine.
- Now, bring the charged sphere into the interior of the pail on top of the first electroscope.
- As shown in the video below - you may need to repeat this process more than once to fully charge the pail.
***** Part 2 *****
- Use the second proofing sphere to attempt to remove charge from the center of the pail, while taking care not to touch the top edges of the pail.
- Then touch the second discharge sphere to the second electroscope, which is uncharged at this point.
***** Part 3 *****
- Finally, attempt transfer charge from the outside of the pail to the second electroscope.
- This final step may need to be repeated more than once to fully charge the second electroscope.
- Even with repeating this final step multiple times - at best you'll observe only a small deflection of the needle on the 2nd electroscope.
Last Update 6/24 - University of Texas at Austin Physics Dept.
- All Rights Reserved.
