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BunDa4Th

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**Help! Not sure what I am doing wrong**

A 11.4 g bullet is fired horizontally into a 94 g wooden block initially at rest on a horizontal surface. After impact, the block slides 7.5 m before coming to rest. If the coefficient of kinetic friction between block and surface is 0.650, what was the speed of the bullet immediately before impact? m/s

first thing i did was find the block speed

t = sqrt((7.5)(.65)/9.8)

t = .7053

then i did

V = deltax/t = 7.5/.7053 = 10.6338

mv_1 + Mv_2 = (m + M)V

V = 98.31 which is incorrect but answer is within 10% of the correct value.

I am not sure if I am doing this correctly or I am just completely off.