Electric Charges and Fields Test - 18

For a system of two charges under the action of centripetal and centrifugal forces, angular momentum remains constant. This is the same as Kepler’s law of planetary motion.

According to quantization of charge, the charge of any system is an integral multiple of the charge of electron which is the least amount of charge on any system.

The dielectric constant of metal is infinite. Metals are those materials which have abundance of valance electrons.

We know that electric field of an ideal spherical shell with uniformly distributed charge is zero inside the shell and equal to EF of a point charge on its centre.

When we calculate the EF for a point on the surface of shell, it is equal to half of EF of same point charge EF.

• The electric field is zero inside a conductor. Just outside a conductor, the electric field lines are perpendicular to its surface, ending or beginning on charges on the surface.
• Any excess charge resides entirely on the surface or surfaces of a conductor.

Since the potential at each point of an equipotential surface is the same, the potential does not change while we move a unit positive charge from one point to another. Therefore work done in the process is zero.

Force on electron

|F| = qE = eE = mg

E = m/ge