Electrostatics ...

The charges on two spheres are +7µC and – 5µC respectively. They experience a force F. If each of them is given and additional charge of –2µC, the new force of attraction will be

Two equally charged, identical metal spheres A and B repel each other with a force \'F\' The spheres are kept fixed with a distance ‘r’ between them. A third identical, but uncharged sphere C is brought in contact with A and then placed at the mid-point of the line joining A and B. The magnitude of the net electric force on C is

Two charges of equal magnitudes and at a distance r exert a force F on each other. If the charges are halved and distance between them is doubled, then the new force acting on each charge is

An infinite number of charges, each of charge 1µC, are placed on the x-axis with co-ordinates x = 1, 2, 4, 8, ...... ∞. If a charge of 1C is kept at the origin, then what is the net force acting on 1C charge

The top of the atmosphere is at about 400 kV with respect to the surface of the earth, corresponding to an electric field that decreases with altitude. Near the surface of the earth, the field is about 100 Vm^–1. Still, we do not get an electric shock as we step out of our house into the open house because (assume the house to be a steel cage so that there is no field inside)

Four metal conductors having different shapes
1. A sphere
2. Cylindrical
3. Pear
4. Lightning conductor
are mounted on insulating stands and charged. The one which is best suited to retain the charges for a longer time is

Identify the wrong statement in the following. Coulomb\'s law correctly describes the electric force that

Which of the following will represent Coulomb\'s law?

A comb run through one\'s dry hair attracts small bits of paper. This is due to

Two charges +6µC and + 15µC are placed along the x-axis at x = 0 and x = 2m respectively. A negative charge is placed between them such that the resultant force on it is zero. The negative charge is placed at