A point charge Q is placed at a distance r on the axial line of a short electric dipole. The electrostatic force experienced by the charge is F . If the distance of the point charge from the center of the dipole is doubled to 2r , the new force experienced by it will be:

Step-by-step solution

The electric field E on the axial line of a short electric dipole at a distance r from its center is given by E = 1 4 ₀ 2p r^3 . The force experienced by the point charge Q is F = QE . Thus, F 1 r^3 . When the distance is doubled ( r' = 2r ), the new force F' becomes: F' 1 (2r)^3 = 1 8r^3 Therefore, F' = F 8 . Answer: F 8