Banner 0
Banner 1
Banner 2
Banner 3
Banner 4
Banner 5

Q.

The diagram shows a small bead of mass m carrying charge + q at P. The bead can freely move on a smooth fixed ring placed on a smooth horizontal plane. In the same plane, a charge + Q has also been fixed as shown. The potential at the point P due to + Q is  V. The speed with which the bead should be projected from the point P so that it can complete a circle along the ring, should be greater than

Question Image

see full answer

Start JEE / NEET / Foundation preparation at rupees 99/day !!

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!
An Intiative by Sri Chaitanya

a

6qVm

b

3qVm

c

qV6m

d

qVm

answer is A.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

As the bead moves form P to M, its distance from fixed charge Q decreases; therefore, its potential energy increases. It has smallest speed at M. For completing the circle, KE at M must be > 0.
   KEM+kqQa=12mu2+kQq4a
It is given that  kQq4a=V
   KEM+4qV=12mu2+qV
 KEM=12mu23qV
 KEM>0
     12mu2>3qV
   u>6qVm
Question Image
 

Watch 3-min video & get full concept clarity

Best Courses for You

JEE

JEE

NEET

NEET

Foundation JEE

Foundation JEE

Foundation NEET

Foundation NEET

CBSE

CBSE

score_test_img

Get Expert Academic Guidance – Connect with a Counselor Today!

whats app icon