Electric Charge...

Two small objects X and Y are permanently separated by a distance 1 cm. Object X has a charge of $$+1.0\mu C$$ and object Y has a charge of $$-1.0\mu C$$. A certain number of electrons are removed from X and put onto Y to make the electrostatic force between the two objects an attractive force whose magnitude is 360 N. Number of electrons removed is :

Two particles with identical positive charges and a separation of $$2.5\times 10^{-2}m$$ are released from rest. Immediately after their release, particle 1 has acceleration whose magnitude is $$4\times 10^{3}ms^{-2}$$. Particle 1 has a mass of $$9\times 10^{-6}kg$$. Then each of the particle has charge of :

A point charge $$Q_{1}$$ exerts some force on a second point charge $$Q_{2}$$. If a 3rd point charge $$Q_{3}$$ is
brought near, the force of $$Q_{1}$$ exerted on $$Q_{2}$$(Without changing their respective positions):

If two point charges of 1 coulomb each are placed 1 km apart in vaccum, the force between them will be:

Electric lines of force are:

A charge of $$-30 \mu C$$ is placed at 50 cm from another charge of $$+25\mu C$$ is vacuum. The force between them is:

If the force between two charged objects is to be left unchanged, even though the charge on one of the objects is halved, keeping the other the same, the original distance of separation 'd' should be changed to:

Two particles having charges $$q_1$$ and $$q_2$$ when kept at a certain distance, exert a force F on each other. If the distance between the two charges is reduced to half then the force exerted on each other would be:

If the force between two charged objects separated by a distance d is to be left unchanged even though the charge on one of the objects is halved, keeping other the same, the new distance of separation becomes :

If two electrons are separated by a distance of $$0.5\mathring { A }$$, then the ratio of coulomb force and weight of the electron is approximately :