Chapter 4, Problem 8RAT

The net force on a kicked football can be zero when

(a) action and reaction both act on the ball.

(b) it is kicked by two feet with equal and opposite amounts of force.

(c) it is kicked in the same direction by two feet.

(d) None of these.

To determine

The correct option for the statement "The net force on a kicked football can be zero when".

Answer to Problem 8RAT

The correct option for the statement "The net force on a kicked football can be zero when" is option (b).

Explanation of Solution

If a person kicks a ball, he applies some action force to the ball. But in a given case,the resultant net force acting on the ball would be zero in magnitude. Following Newton's law of action force and reaction force, it is only possible if another force of equal amount but opposite in direction is applied to the ball.

Thus, when two persons hit a ball from opposite sides of the same magnitude, they cancel each other's force, and the net resultant on the ball becomes zero. If the applied load is not equal in magnitude, the resultant net force becomes equal to the applied force difference, not zero.

Conclusion:

Therefore, the correct option for the statement "The net force on a kicked football canbe zero when" is option (b).