How many electrons need be removed from a metal sphere of 0.05 m radius so that it acquires a charge of `4 xx 10^-15` C ? `e = 1.6 xx 10^-19` C.

4xx10^16 electrons are removed from a conductor. The conductor acquires a charge of

When 10^19 electrons are removed from a neutral metal plate, the elctric charge on it is

The number of electrons removed from a body in order to produce positive charge of 5 xx 10^-19 coulomb on it, will be

What will be the no. of electrons removed from a body in order to produce a positive charge of 48 xx 10^-20 coulomb on it?

A metallic wire of diameter 0.02m contains 1028 free electrons per cubic meter. Find the drift velocity for free electrons, having an electric current of 100 amperes flowing through the wire. (Given : charge on electron = 1.6 xx 10^-19 C)

In a chamber , a uniform magnetic field of 6.5 G (1 G = 10^-4 T) is maintained. An electron is shot into the field with a speed of 4.8 xx 10^6 ms^-1 normal to the field. Explain why the path of the electron is a circle. Determine the radius of the circular orbit, (e=1.6 xx 10^-19 C,m-e=9.1 xx 10^-31 kg)

A current of 800 mA is passed through an electric lamp for one minute. Find the number of electrons passing through it if the charge of electron is 1.6 xx 10^-19 C.

4xx10^10 electrons are removed from a neutral metal sphere of diameter 20 cm placed in air. The magnitude of the electric field (in NC^-1 ) at a distance of 20 cm from its centre is

A simplified model of hydrogen atom consists of an electron revolving about a proton at a distance of 5.3 xx 10^-1 1m. The charge on a proton is +1.6 xx 10^-19 C. Calculate the intensity of the electric field due to proton at this distance.