The graph below approximates the force applied to a tennis b
     The graph below approximates the force applied to a tennis ball by a racket during the time they are in contact.  What impulse does the ball receive from the racket? 
  
  Solution
Here impulse is given by
Impulse= area under the graph
I=A1+A2+A3
Area of traingle A=(1/2)bh
Area of rectangle =L*W
I=(1/2)*60*0.02 +0.02*60+(1/2)*0.02*60
I=2.4 N-s

