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a ball of mass 0.2 kg strikes a wall when moving horizontally at 12m/s. if the ball rebounds horizontally at 8m/s, find the impulse exerted by the wall
if yes j is:\[\Delta p=j \rightarrow p _{2}-p _{1}=j\] \[p _{2}=mv _{f} \] \[p _{1}=mv _{i}\]so j yeilds -0.8 neg sign for direct of j i thnk
I=ft ft = mv-mu ft = (0.2)(-8)-(0.2)(12) = -2.56N*s... i think so..
sorry...the answer is -4J / 4N*s