Coulombs Law

Two positive ions, each carrying a charge , are separated by a distance . If is the force of repulsion between the ions, the number of electrons missing from each ion will be:
( is the charge on an electron)

1.		2.
3.		4.

Two pith balls carrying equal charges are suspended from a common point by strings of equal length, the equilibrium separation between them is (as shown in Fig. I). Now, as shown in Fig. II, the strings are rigidly clamped at half the height. The equilibrium separation between the balls now becomes:

1.		2.
3.		4.	none of the above

Suppose the charge of a proton and an electron differ slightly. One of them is the other is If the net of electrostatic force and gravitational force between two hydrogen atoms placed at a distance (much greater than atomic size) apart is zero, then is of the order of?
(Given the mass of hydrogen ${\mathrm{}}_{}$ $$)
1.
2.
3.
4.

Two point charges and having charges and respectively, are placed at a certain distance apart and the force acting between them is If charge of is transferred to then the force between the charges becomes:

1.		2.
3.		4.

The acceleration of an electron due to the mutual attraction between the electron and a proton when they are apart is:

1.
2.
3.
4.

Two identical charged conducting spheres and have their centres separated by a certain distance. Charge on each sphere is and the force of repulsion between them is A third identical uncharged conducting sphere is brought in contact with sphere first and then with and finally removed from both. New force of repulsion between spheres and (Radii of and are negligible compared to the distance of separation so that for calculating force between them they can be considered as point charges) is best given as:

1.		2.
3.		4.