Question

A(n) 0.394 kg soccer ball approaches a player horizontally with a speed of 12.7 m/s. the player illegally strikes the ball with her hand and causes it to move in the opposite direction with a speed of 24.4 m/s. what is the magnitude of the impulse delivered to the ball by the player? answer in units of kg · m/s.

Answer 1

A momentum is caused by a body along with its velocity .It is an vector quantity since it dealt with direction. When a change in momentum for a defined time it called as impulse . ---> eqn 1 According to Newton's second law, the force is defined as rate of change of momentum. ie force F = dm/ dt where dm = change in momentum ; dt = change in time, ; therefore dm = F* dt. here from eqn1 dm is now defined as impulse. Ans : initial momentum = m * velocity = 0.394 kg*12.7 = 5.0038kgm/s momentum in opp direction = m*velocity =0.394kg* 24.4m/s = 9.6136 impulse = change in momentum = 5.0038-9.6136 = - 4.6098 the resultant impulse is = -4.6098; the negative symbol shows the direction that moves in the opposite direction,