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## Jonask Group Title work done to move a capacitor in parrallel a distance x one year ago one year ago

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1. yrelhan4 Group Title

*

2. Jonask Group Title

|dw:1364587708013:dw|

3. yrelhan4 Group Title

I was just tagging myself.

4. Jonask Group Title

herre i mean to move it away from the other by applying a force $F_A$

5. Jonask Group Title

*

6. electrokid Group Title

work done = change in internal energy

7. electrokid Group Title

1) Energy in a capacitor $$U={1\over2}{Q^2\over C}$$

8. Jonask Group Title

F=qE

9. electrokid Group Title

2) what changes when you separate the plates? capacitance: $C={\epsilon_0kA\over d}$

10. electrokid Group Title

so, $U={1\over2}{Q^2d\over\epsilon_0kA}$

11. electrokid Group Title

W = final energy - initial energy

12. electrokid Group Title

remember that Q does not change in this case, but C and V do

13. electrokid Group Title

@Jonask you are increasing the separation between the plates, right?

14. Jonask Group Title

yes i was hoping for $dW=Fdx$

15. Jonask Group Title

i dont see x in you expressions above

16. Jonask Group Title
17. Jonask Group Title

i would like us to do it intergration way

18. Jonask Group Title
19. electrokid Group Title

you do not necessarily have to use the integration way. total work done is independent of path followed; depends on the initial and final states only!