A parallel plate capacitor is charged by connecting the plates to a battery. The battery remains connected and a glass plate is inserted between the plates of the capacitor then

Three capacitors of capacitance 3μF, 9μF and 18 μF are connected first in series and then in  parallel. The ratio of the equivalent  capacities in the two cases is 

The unit of electric field is

Two charged balls attract each other with a certain force.If they are allowed to touch and then separated to the same distance appart the two balls will

A charged particle of mass 8 gm remains stationary on a vertical electric field.10⁴KN/c.The amount of charge is

A parallel plate capacitor is charged and the charging battery is then disconnected. If the plates of the capacitor are moved farther apart by means of insulating handles.

An electron falls between two parallel plate of separation 2m, where a uniform electric field 2.5v/m exists. The energy gained by electron is equal to

A 500μF capcitor is charged at a steady rate of 100μc/s. The potential difference across the  capacitor will be 10v after an interval of 

Two spherical conductors B and c of equal radii and carrying equal charge on them repel each other with a force F when kept apart at some distance.A third spherical conductor having some redius as that of B but uncharged is brought in contact with B and then with C and removed away from both.The new force of repulsion between B and C

An isolated metal sphere of radius R is given a charge q. its potential energy will be