e-e-

e-

e-

e-e-

e-

e-

e-

e-

p+ p+ p+

• Connecting two parallel plates to a battery produces uniform electric field

the electric field strength will depend on the distance between the plates and the voltage of the battery

p+

d

VE V = voltage of battery

d = distance between the plates in m= magnitude of electric field strength in V/mE

C

N

mC

mN

mC

J

m

V

This formula only applies to parallel plates!

•electric field strength between the plates is uniform (a charge placed at any point in the field will experience the same force)•the electric field outside of the plates is 0•the magnitude of the electric field depends on the magnitude of the charge on each plate •field lines point from the + plate to the - plate

Examples Two parallel plates are 3.00 cm apart and have a potential difference of 7.10 x 103 V. If a charged object (q = 4.80 x 10-15 C) is placed in the field, what is the electric force acting on it?

Nx.Cx.)C/Nx.(

FqE

q

FE

m/Vx.mx.

Vx.E

d

VE

e

e

9155

52

3

10141108041036672

103667210003

10107

2. A pair of oppositely charged parallel plates are separated by 5.33 mm and connected to a 600 V source of potential difference.

a) What is the magnitude of the electric field between the plates?

b) What is the magnitude of the force acting on an electron placed anywhere between the plates?

c) How much work must be done on the electron to move it to the negative plate if it is originally placed 2.90 mm from the positive plate?