Example -1
Find the momentum of the object of mass of .5 kg and moving with velocity 10 m/s?
Solution
Momentum is given by
$p= mv = .5 \times 10 = 5 kgms^{-1}$
Example -2
A tennis player hit the ball at the
Speed 40 m/s . The mass of the ball is .05 kg and it was in contact with racket for 4 ms. Find the force applied by the tennis player?
Solution
$F = \frac {dp}{dt}$
Initial momentum =0
Final momentum= .05 x 40 = 2 kgm/s
$F = \frac {2 -0}{4 \times 10^{-3}} = 500 N$