Question

A ball is thrown up at an angle with the horizontal. Then the total change of momentum by the instant it returns to ground is

• A. acceleration due to gravity $\times$ total time of flight
• B. weight of the ball $\times$ half the time of flight
• C. weight of the ball $\times$ total time of flight
• D. weight of the ball $\times$ horizontal range

Answer 1

Answer: (C)

Change in momentum of the ball
$=mv\sin \theta -(-mv\sin \theta )=2mv\sin \theta$
$=mg\times \frac{2\nu \sin \theta }{g}$
$=$ weight of the ball $\times$ total time of flight