If a negative point charge is placed at P without moving the original charges, the net electrical force the charges ±Q will exert on it is

The particle P moves directly upwards

Explanation:

Lets designate the negative point charge at point P as particle P

The +Q charge will exert an attractive force on the particle P.

The -Q charge will exert a repulsive force on the particle P

The +Q charge exerts an upwards and leftward force on particle P

The -Q charge exerts an upwards and rightward force on particle P

Since the charges are equidistant from the particle P, and are of equal magnitude, the rightward force and the leftward force will cancel out, leaving just the upward force on the particle P.

The effect of the upward force is that the particle P moves directly upwards

the second one and the forth one are in the purple because they are opinions and the rest are in the yellow

explanation:

pretty sure it's false