Answer:
Newton's second law of motion accounts for the "A ball hit by a man travels faster than one hit by a boy."
Step-by-step explanation:
Second law of motion relates the force exerted by an object and the acceleration of that object, of a given mass.
Mathematically it is F = ma where F is the force, m is the mass and a is the acceleration of an object.
Hence according to that , for a given mass, it can be seen that force is directly proportional to the acceleration. More force implies more acceleration. Lesser force implies lesser acceleration and so moves slowly.
That's why when the same ball is hit by the father with a greater force, it travels faster than when hit by the child with a lesser force.