The figure shows all the forces acting on an object. What can you tell about the velocity of the object at this instant?
The object is moving downwards.
The object is moving upwards.
The object is slowing down.
The object is speeding up.
By looking at the free body diagram we can tell the acceleration is downward, but this only tells us how the velocity is changing, it does not tell us anything about the magnitude or direction of the velocity at this instant.