Give the magnitude and direction of the net force acting on a rain drop falling freely with a constant speed 5m/s.

When the rain is falling down with constant speed, its acceleration is zero. Hence, according to first law of motion net force acting on rain drop is zero.

When rain drop is freely falling it posses accelerated motion, hence velocity can not be remain constat. In that sense net force on rain drop is 'mg' which wil be acting on downwards direction.