5.3 Electric Potential

1. 5.3 Electric Potential The van de Graaff generator Work is done in charging the metal dome? Why?

2. 5.3 Electric Potential The van de Graaff generator Work is done in charging the metal dome? Why? ‘like’ charges are being moved closer to each other

3. 5.3 Electric Potential The van de Graaff generator Work is done in charging the metal dome? Why? ‘like’ charges are being moved closer to each other The electric potential of the dome is increasing

4. 5.3 Electric Potential o o The electric potential V at a point P in an electric field is defined as: ‘the work done per unit positive charge on a positive small test charge when it is moved from infinity to that point’ P + + + r

5. 5.3 Electric Potential o o o o The electric potential V at a point P in an electric field is defined as: ‘the work done per unit positive charge on a positive small test charge when it is moved from infinity to that point’ Unit: V or JC-1 work done = electric potential energy gained P + + + r Zero Potential energy at

6. 5.3 Electric Potential o o o o The electric potential V at a point P in an electric field is defined as: ‘the work done per unit positive charge on a positive small test charge when it is moved from infinity to that point’ Unit: V or JC-1 work done = electric potential energy gained P + + + r Zero Potential energy at

7. The electric potential at point P: Vp = Ep Q So electric potential energy Ep=Vp Q o o o o 1000V Electric Potential P + 1ųC + + + r Zero Potential energy at

8. The electric potential at point P: Vp = Ep Q So electric potential energy Ep=Vp Q o o o o electric potential energy Ep=Vp Q Ep=1000 Ep= 1mJ of a test charge moving from infinity to where the potential is 1000V 1ųC x 1ųC ( work done in moving this charge from infinity to point P) 1000V Electric Potential P + 1ųC + + + r Zero Potential energy at

9. The electric potential at point P: Vp = Ep Q So electric potential energy Ep=Vp Q o o o o If the test charge is moved in a field from where the potential is V1 to a position where the potential is V2 then the work done: ΔW = Q ( V2 -V1) electric potential energy Ep=Vp Q Ep=1000 Ep= 1mJ of a test charge moving from infinity to where the potential is 1000V 1ųC x 1ųC ( work done in moving this charge from infinity to point P) 1000V Electric Potential P + 1ųC + + + r Zero Potential energy at

10. Equipotentials: Electric potential Energy: Ep=QVp are lines joining points of constant potential. They cross field lines at 90o. then the work done: ΔW = Q ( V2 -V1) = (400 - 1000) = x - 600 = - 1.2 x 10-3 J + 2ųC + 2ųC

11. Equipotentials: Electric potential Energy: Ep=QVp are lines joining points of constant potential. They cross field lines at 90o.

12. Potential relative to the negative plate Distance X Distance X E = - ΔV ΔX

13. Potential relative to the negative plate Distance X Distance X E = - ΔV ΔX

14. Potential relative to the negative plate Distance X Distance X E = - ΔV ΔX

15. Potential relative to the negative plate Distance X Distance X E = - ΔV ΔX

16. Potential relative to the negative plate Distance X Distance X E = - ΔV ΔX