Answer:
The net force causes an increase in acceleration because without the force, the ball's movement would remain the same.
Step-by-step explanation:
When a force is applied to a body in motion, the effect is to give the body an acceleration. The acceleration can be positive if the force is in the direction of motion of the body or negative if it is in opposite direction of the direction of motion of the body. Without a force applied to a body, the body will continue to move in a constant velocity as stated in Newton's first law of motion. In this case, the non-zero net force will cause an increase in the acceleration of the body, because without this force, the ball's movement will stay the same according to Newton's first law of motion.