What are the velocities of the particles after a perfectly inelastic collision?

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In a perfectly inelastic collision between two particles, where particle 1 with mass m moves with initial velocity v and particle 2 with mass 3m is stationary, the final velocity of both particles after the collision can be determined using conservation of momentum. The equation m_1v_1 + m_2v_2 = (m_1 + m_2)v_f is applied, leading to the conclusion that v_f equals (1/4)v. The initial velocity of particle 1 is v, and particle 2's initial velocity is 0. The final velocity of the combined mass after the collision is thus (1/4)v.
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Homework Statement



Particle 1 has initial velocity v, directed to the right, and particle 2 is initially stationary.
Let the mass of particle 1 be m and the mass of particle 2 be 3m. If the collision is perfectly inelastic, what are the velocities of the two particles after the collision?

Homework Equations



m_{}1v_{}1 + m_{}2v_{}2= (m_{}1+m_{}2)v

The Attempt at a Solution



m_{}1v_{}1 = (m + 3m)v
v_{}1 = ((4m)v)/m

so I get v_{}1 and ]v_{}2 (since they are stuck together) to be 4v, but it says I'm off by a multiplative factor. Any ideas?
 
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You solved for the wrong velocity. Solve for v_f, not v_1. v_1 is given as "v".
 
yep, it's (1/4)*v, thanks.
 
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