A non-conducting disc of radius a and uniform positive surface charge density `sigma` is placed on the ground, with its axis vertical. A particle of mass m and positive charge q is dropped, along the axis of the disc, from a height H with zero initial velocity. The particle has `q//m=4 in_0 g//sigma`
(a) Find the value of H if the particle just reaches the disc.
(b) Sketch the potential energy of the particle as a function of its height and find its equilibrium position.

A nonconducting disk of radius a and uniform positive surface charge density sigma is placed on the ground, with its axis vertical. A particle of mass m and positive charge q is dropped, along the axis of the disk, from a height H with zero initial velocity. The particle has q//m = 4 epsilon_(0) g// sigma . (i) Find the value of H if the particle just reaches the disk. (ii) Sketch the potential energy of the particle as a function of its height and find its equilibrium position.

A uniformly charged disc of radius R having surface charge density sigma is placed in the xy plane with its center at the origin. Find the electric field intensity along the z-axis at a distance Z from origin :

A non-conducting thin disc of radius R charged uniformly over one side with surface density s rotates about its axis with an angular velocity omega . Find (a) the magnetic induction at the centre of the disc, (b) the magnetic moment of the disc.

A non-conducting thin disc of radius R charged uniformly over one side with surface density sigma , rotates about its axis with an angular velocity omega . Find (a) the magnetic field induction at the centre of the disc (b) the magnetic moment of the disc.

A circular ring of radius R with uniform positive charge density lambda per unit length is located in the y-z plane with its centre at the origin O. A particle of mass m and positive charge q is projected from the point P (Rsqrt3, 0, 0) on the positive x-axis directly towards O, with an initial speed v. Find the smallest (non-zero) value of the speed v such that the particle does not return to P.

A non-conducting semi circular disc (as shown in figure) has a uniform surface charge density sigma . The ratio of electric field to electric potential at the centre of the disc will be

A flat disc of radius R charged uniformly on its surface at a surface charge density sigma . About its central axis of rotation it rotates at an angular speed omega . Find the magnetic moment of disc due to rotation of charges.

Positive charge Q is distributed uniformly over a circular ring of radius R. A particle having a mass m and a negative charge q, is placed on its axis at a distance x from the centre. Find the force on the particle. Assuming x ltltR, find the time period of oscillation of the particle if it is released from there.

A smooth chute is made in a dielectric sphere of radius R and uniform volume charge density. rho . A charge particle of mass m and charge -q is placed at the centre of the sphere. Find the time period of motion of the particle?