|
Size: 1023
Comment:
|
Size: 1119
Comment:
|
| Deletions are marked like this. | Additions are marked like this. |
| Line 3: | Line 3: |
attachment:BatteryAndSeparableCapacitor.jpg |
|
| Line 10: | Line 12: |
| Discussion: Q=CV. The battery charges the plates to 12V, however, once the battery is removed, the charge Q on the plates is fixed. As the plates are separated, the capacitance C decreases. Therefore the voltage V must increase. Since CV is fixed, the energy (1/2 CV^2) increases as the plates are separated. It takes work to separate the plates. | If lecturing to a large class, project a camera view of the Electrometer on a screen. |
| Line 12: | Line 14: |
| attachment:BatteryAndSeparableCapacitor.jpg | Discussion: Q=CV. The battery charges the plates to 12V, however, once the battery is removed, the charge Q on the plates is fixed. As the plates are separated, the capacitance C decreases. Therefore the voltage V must increase. Since CV is fixed, the stored energy (1/2 CV^2) increases as the plates are separated. It takes work to separate the plates. |
Battery and Separable Capacitor
attachment:BatteryAndSeparableCapacitor.jpg
The separable parallel-plate capacitor and the battery are in the [:ElectrostaticsCabinet:Electrostatics Cabinet], A4.
The Electrometer is in the [:ElectrostaticsCabinet:Electrostatics Cabinet], B1.
Connect the parallel-plate capacitor to the Electrometer. Charge the capacitor to 12V using the battery. Vary the spacing between the plates. The voltage on plates goes up as the plate spacing goes up.
If lecturing to a large class, project a camera view of the Electrometer on a screen.
Discussion: Q=CV. The battery charges the plates to 12V, however, once the battery is removed, the charge Q on the plates is fixed. As the plates are separated, the capacitance C decreases. Therefore the voltage V must increase. Since CV is fixed, the stored energy (1/2 CV^2) increases as the plates are separated. It takes work to separate the plates.
[:Capacitance:Capacitance]
[:Demonstrations:Demonstrations]
[:Instructional:Home]