Home
Class 12
PHYSICS
A Circular ring of radius 3a is uniforml...

A Circular ring of radius `3a` is uniformly charged with charge `q` is kept in `x-y` plane with center at origin. A particle of charge `q` and mass `m` is projected frim `x=4` towards origin. Find the minimum speed of projection such that it reaches origin.

A

`sqrt(2)/m (1/15 q^(2)/(4 pi epsilon_(0)a))^(1//2)`

B

`sqrt(2/m)(2/15 q^(2)/(4pi epsilon_(0)a)^(1//2))`

C

`sqrt(2/m)(4/15 q^(2)/(4pi epsilon_(0)a)^(1//2))`

D

`sqrt(2/m)(1/5 q^(2)/(4pi epsilon_(0)a)^(1//2))`

Text Solution

Verified by Experts

The correct Answer is:
B

From energy conservation,
`U_(1) + k_(1) = U_(f) + k_(f)`
`(k(q)(q))/sqrt((3a)^(2)+(4a)^(2)) + 1/2mv_("min")^(2) =(k(q)(q))/(3a)+0 rArr V_("min") = sqrt(2/m)(2/15 q^(2)/(4pi epsilon_(0)a)^(1//2))`
Promotional Banner

Topper's Solved these Questions

  • JEE MAIN REVISION TEST -14

    VMC MODULES ENGLISH|Exercise PHYSICS (SECTON 2)|5 Videos

  • JEE MAIN REVISION TEST - 7|JEE - 2020

    VMC MODULES ENGLISH|Exercise Physics (Section -2) (Numerical Value Type)|5 Videos

  • JEE MAIN REVISION TEST -17 (2020)

    VMC MODULES ENGLISH|Exercise PHYSICS|25 Videos

Similar Questions

Explore conceptually related problems

A circular ring of radius R and uniform linear charge density +lamdaC//m are kept in x - y plane with its centre at the origin. The electric field at a point (0,0,R/sqrt(2)) is

A circular ring of radius R with uniform positive charge density lambda per unit length is located in the y z plane with its center at the origin O. A particle of mass m and positive charge q is projected from that point p( - sqrt(3) R, 0,0) on the negative x - axis directly toward O, with initial speed V. Find the smallest (nonzero) value of the speed such that the particle does not return to P ?

A positively charged ring is in y - z plane with its centre at origin . A positive test charge q_(e ) , held at origin is released along x axis, then its speed

In the figure shown there is a large sheet of charge of uniform surface charge density 'sigma' .A charge particle of charge '-q' and mass 'm' is projected from a point A on the sheet with a speed 'u' with the angle of projection such that it lands at maximum distance from A on the sheet. Neglecting gravity, find the time flight

Two identical coaxial rings each of radius R are separated by a distance of sqrt3R . They are uniformly charged with charges +Q and -Q respectively. The minimum kinetic energy with which a charged particle (charge +q ) should be projected from the centre of the negatively charged ring along the axis of the rings such that it reaches the centre of the positively charged ring is

There are two concentric and coplanar non-conducting rings of radii R and 4R . The charge is distributed uniormly on both rings. The charge on smaller ring is q and charge on large ring is -8q . A particle of mass 10g and charge -q is projected along the axis from infinity. What is the minimum speed of charge at infinity to reach the common centre of rings (take (Kq^(2))/R=(2sqrt(5))/3J )

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

A uniformly charged ring having total charge Q and of radius R is fixed in such a way so that plane of the ring is horizontal. A charged particle of charge q and mass m is in equilibrium at any point lying on y -axis under the combined forces of electric field and earth's gravitational field. Choose the correct statements

A charge q = -2.0 muC is placed at origin. Find the electric field at (3 m, 4 m, 0) .

A thin circular wire of radius r has a charge Q. If a point charge q is placed at the centre of the ring, then find the increase in tension in the wire.