Question

A certain uniformly-charged ring has a radius of 24.0 cm and the electric potential (relative to points very far away) at its center is 382 V. What is the electric potential on its axis 18.0 cm from the plane of the ring?

options:

a) 197 V

b) 287 V

c) 306 V

d) 364 V

e) 219 V

Answer 1

The formula for the electric potential (relative to points very far away) at its center is kQ/r. The formula for the electric potential (relative to points very far away) on ring's axis from the plane of the ring is equal to kQ /?(x^2 + r^2), where r is the radius of the ring and x is the distance of the point on the from the center of the ring.

So, the required potential is equal to 382*(r/?(x^2 + r^2))

Calculating by substituting the given values:- 382*(24/?(24^2 + 18^2)) = 306 V