For a ball moving on a smooth frictionless surface, choose the appropriate option that will make the following statements physically correct.
If no net force is applied on the ball, the velocity of the ball will remain the same/increase/decrease.
remain the same
If a net force is applied on the ball in the direction of its motion, the magnitude of the velocity of the ball will remain the same/increase/decrease.
increase
If a net force is applied on the ball in a direction opposite to the direction of its motion, the magnitude of the velocity of the ball will remain the same/increase/decrease.
decrease
Explanation
According to Newton's first law of motion as described in the context, if the net force acting on an object is zero, it will continue moving with a constant velocity, meaning the velocity remains the same. When a net force is applied in the direction of the ball's motion, it accelerates the ball, causing the magnitude of its velocity to increase. Conversely, when a net force is applied opposite to the direction of motion (similar to how friction acts), it opposes the motion and causes the magnitude of the velocity to decrease, eventually bringing the object to rest.