Find the strength and direction of the net force on an apple weighing 2 n, neglecting air resistance, in each?
the apple is held at rest in your hand.
the apple is falling to the ground.
the apple is moving upward, just after you threw it upward.

a) F=0N

b) F=2N pointing to the ground.

c) F=2N pointing to the ground.

Explanation:

a) The apple is at rest at your hand. This is because the force of gravity is pulling the apple down with a force of 2N, but your hand is aplying to the apple an equal but opposite force of 2N that is the normal force, which points up. If we sum these forces: F=2N-2N=0N in the vertical axis. This null force has no preferred direction.

b) The only force acting over the apple is the force of gravity, which has a value of F=2N for this apple and always points to the ground.

c) Even if the apple is moving upwards, the only force acting on it is the force of gravity, which has a strength of F=2N for the apple and points always to the ground.