Two protons exerts a nuclear force on each other, the distance between them is

Q. Two protons exerts a nuclear force on each other, the distance between them is

Q. Mark the correct statements:
(a) The nuclear force between two protons is always greater than the electromagnetic force between them.
(b) The electromagnetic force between two protons is always greater than the gravitational force between them.
(c) The gravitational force between two protons may be greater than the nuclear force between them.
(d) Electromagnetic force between two protons may be greater than the nuclear force acting between them.

Q. Two point charges $Q_1$ and $Q_2$ exerts force $F$ on each other, when kept at certain distance apart. If the charge on each particle is halved and the distance between them is doubled, then the new force between the two particles would be

Q. Two protons attract each other when the distance between them is

Q. The nucleus of helium atom contains two protons that are separated by distance $3.0\times {10}^{-15}m$. The magnitude of the electrostatic force that each proton exerts on the other is: