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## Homework Statement

A 0.057 kg tennis ball moving west at 24 m s is hit in the opposite direction east with a tennis racket. The force acting on the ball during the hit is shown in the graph below.

What is the magnitude of the final momentum of the tennis ball?

**A. 0.63 kgm s**B. 1.37 kgm s C. 1.80 kgm s D. 3.37 kgm s

## Homework Equations

f(tf-ti)=m(vf-vi)= change in momentum=impulse[/B]

## The Attempt at a Solution

so I assumed that I could find final velocity going east by doing this

f ( tf - ti )= m ( vf - vi )

80 ( 0.06-0.02 ) = 0.057 ( vf - (-24) )

3.2 = 0.057 ( vf - (-24) )

56.14 = vf - (-24)

vf=32 m/s

so momentum right is (0.057)(32)=1.824 kg*ms

left is (0.057)(-24)= -1.368 kg*ms

final is 1.824 + (-1.368) = .456kg*ms to the right

this is incorrect so I'm not sure where i went wrong, i'm sure its simple but it escapes me.

thanks for any insight