Download ELECTRIC POTENTIAL

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)
q- Charge(coulombs)
V-Potential difference
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=Ed
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
+ + + + + + + +
q
q
q
- - - - - - -
Electric field is uniform regardless of
where the charge is placed