5A10.09 - Rods and Fur or Silk with Electroscope
To demonstrate the two types of charges, positive and negative, and how an electroscope works to measure the charge.wa
Grab two rods of each material, Teflon and Nylon, and set them on a v-stand with the appropriate cloth next to or underneath them. Place the electroscope within arms reach of the rods and fur or silk. Set up a camera to view the electroscope. The electroscope should be grounded with a banana cable and plug and plugged into the cart.
The rods are dielectric with the charges remaining in static position on the surface. To achieve full charge on the rod, you must rub the whole length with the silk or fur. Charge up one rod with the appropriate cloth.
You should see the scope rise to a given value. Then either charge that same rod again and touch the electroscope again and see the scope rise again or charge up the other rod and when you touch the rod to the electroscope, the needle should decrease since the positive and negative charges cancel out. This decreases the overall total charge remaining on the electroscope.
**BY SPECIAL REQUEST**
This demo can be used with an electrophorus plate.