Question

15.
12. A point charge q = 2 uC is at a distance d = 20 cm
from a uniformly charged infinite sheet with a surface
charge density o = 20microC/m².
(a) What is the force on the point charge?
(b) At what point is the resultant field strength zero? ​

Answer 1

Explanation:

An infinite plane metal plate is in the xyxy-plane. A point charge +QQ is placed on the zz-axis at a height hh above the plate. Consequently, electrons will be attracted to the part of the plate immediately below the charge, so that the plate will carry a negative charge density σσ which is greatest at the origin and which falls off with distance ρρ from the origin. Can we determine σ(ρ)σ(ρ)? See Figure