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Question

 How much impulse is given to a 1.20 kg tennis ball that is accelerated from 22.0 m/s to 15.0 m/s

Answer 1

Tennis ball mass m = 1.20 kg

Initial velocity vi = 22 m/s

Final velocity vf = 15 m/s

Change in Velocity Δv = vf - vi

Δv = 15 - 22

Δv = - 7 m/s

Change in Momentum ΔP = Mass * Change in Velocity

ΔP = mΔv

ΔP = (1.2)(- 7)

ΔP =  - 8.4 kg-m/s

By Using Impulse momentum equation : Impulse (FΔt) = Change in Momentum

Impulse (FΔt) = - 8.4 kg-m/s