electric potential. electric potential: energy a charge has due to its position in an electric...
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ELECTRIC POTENTIAL
Electric Potential:
Energy a charge has due to its position in an electric field.
EPE
distance
Electrical Potential Difference• Work done per unit of charge as a charge
moves through a field
V = W/q
W- work(joules) V-Potential difference
q- Charge(coulombs) J/C or Volt
example• A 12 volt battery does 1200J of work
transferring a charge through an electric field. How much charge is transferred?
V = W/q
12V = 1200J/q
q = 100C
Capacitor
• Two parallel plates that collect and store electrical energy to be used at a later time.
Dielectric-Placed in a capacitor to allow it to store more charge
Nonmetallic substance that will allow the electric field to be maintained
Potential Between Parallel Plates
V = E d
V- electric potential (volts)
E- electric field intensity (N/C)
d= distance between plates (m)
Example
A)Two plates of a capacitor are 0.03m apart. What is the potential difference if they have an electric field of 3000N/C?
V= Ed
V= 3000N/C(0.03m)
V= 90Nm/C = 90J/C = 90V
B) What work is needed to move an electron from the (+) plate to the (-) plate of the capacitor?
V=W/q
90V= W/(1.6x10-19C)
W= 1.44x10-17J
Field intensity
+ + + + + + + +
- - - - - - -
Electric field is uniform regardless of where the charge is placed
q
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