Two identical bar magnets are fixed with their centres at a distance d apart. A stationary charge Q is placed at P in between the gap of the two magnets at a distance D from the centre O as shown in the figure The force on the charge Q is

Step-by-step solution

The force of attraction on Q by the north pole of first magnet is F . The force of attraction on the same charge by n the north pole of another magnet must be opposite to that of the first magnet. Thus, they concel the effect of one other and hence force on the charge Q is zero.