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 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 Find the value of H if the particle just reaches the disc.

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 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 non-conducting disc of radius a with 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. Charge per unit mass of the particle is q/m = (4 epsilon_0 g)/(sigma) . (i) Find the value of H if the particle just reaches the disc.

A non-conducting disc of radius a with 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. Charge per unit mass of the particle is q/m = (4 epsilon_0 g)/(sigma) . (ii) Find the height for 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 disc of radius R is uniformly charged with surface charge density sigma . A disc of radius (R )/(2) is cut from the disc, as shown in the figure. The electric potential at centre C of large disc will be

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 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