(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

We are trying to predict the speed of all three blocks at the first instant they all have the same speed using only variables.

2. Relevant equations

fg = mg

fk = -μk(mg) = normal force

a = F/m

t = √(2Δx/a) derived from Δx = Vot + 1/2at^2

v = vo + at

p = mv = m(at)

p1 + p2 = pf (convserve momentum)

3. The attempt at a solution

This is my work and final solution of Vf at the bottom, i treated m1 and m2 as one object then used conservation of momentum to find the final velocity. it just does not seem right, i would have thought it would involve the kinetic friction of m3 somehow. i am assuming this is a perfectly inelastic "collision". But when i think about it more, i am thinking they are all 3 at the same speed the instant the impulse of the 2 moving blocks cause the 3rd block to have a momentum value, thus why i used the conservation of momentum to solve for final velocity. Can anyone guide me as to whether or not my thinking is on the right track?

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# Momentum, Friction, and Velocity, OH MY!

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