A 0.050 kg projectile is launched with a horizontal velocity of 647 m/s from a 4.65 kg launcher moving in the same direction at 2.00 m/s. What is the velocity of the launcher after the projectile is launched? Please show work.

Hi, Ron, I hope you're giving this your best 'shot'.
This is a conservation of linear momentum problem, initial momentum of the system must = the final momentum of the system, where linear momentum, usually denoted as p, is = to mass times velocity, thatis, p=m*v .
the initial momentum of the system is (0.05)(2) + 4.65(2), or 9.4. Therefore
initial momentum = final momentum
9.4 = 0.05(647) + 4.65(V_L)
9.4 - 32.35 = 4.65(V_L)
V_L = - 4.94m/s
The negative sign means the launcher moves at 4.94 m/s backwards.
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