Question

Eight charges each of value q each are placed on a ring of radius R placed in x-y plane with origin at center. -q charge having mass m is projected from z = $\infty$ towards the center of the ring with velocity v. The velocity of -q when it reaches the center of ring is (neglect gravity)

Diagram and Options (Attached)

Class - 12th
Chapter - Electrostatic Potential and Capacitance.

Answer 1

Explanation:

option 'c' is correct

you can learn from the above pic

Answer 2

Answer:

(C)

Explanation:

$U_{i}+ K _{i} = U_{f}+ K _{f} \\0+ \frac{1}{2} mv^2 = \frac{-K8q^2}{R} + \frac{1}{2} mv^2\\therefore ,\\v_{f} =\sqrt{\frac{16Kq^2}{mR} + v^2}$

p.s. v_f is actually v ^(dash) but the system was not taking

PLS MARK AS BRAINLIEST