Question

A ring of radius R has charge -Q distributed uniformly over it. Calculate the charge (q) that should be placed at the center of the ring such that the electric field becomes zero at a point on the axis of the ring. the value of q is​

Answer 1

Answer:

answer 2

Explanation:

The electric field due to a ring of radius R at a point on its axis is E=k(z2+R2)3/2−Qz

Electric field at point P(z=R) is E1=k(R2+R2)3/2−QR=−k22R3QR=−k22R2Q

Electric field at P due to center charge q is E2=kR2q

As the net field at P is zero so 

E1+E2=0

or −k22R2Q+kR2q=0

⇒q=22Q=4Q2

hope it helps

Answer 2

Answer:

didi now i am recovered,