Question (I added a picture): The free-rolling ramp has a mass of 40 kg. A 10 kg crate is released from rest at A and slides down 3.5 m to point B. If the surface of the ramp is smooth, determine the ramp's speed when the crate reaches B. Also, what is the velocity of the crate? This is what I did for finding the velocity of the ramp: 1) \sigma mv1 = \sigma mv2 2) mass ramp * (velocity ramp)1 + mass crate * (velocity crate)1 = mass ramp * (velocity ramp)2 + mass crate *(velocity crate)2 3) 40*Vr + 0 = 40*Vr2 + 10*Vc2 Too many unknowns? This is what I did for finding the velocity of the crate: 1) Vc2^2 = Vinitial^2 + 2*a*(S-Sinitial) = 0 + 2 * 4.905 * 3.5 Vc2 = 5.86 m/s 2) I can substitute this in to the first equation, but I still have too many unknowns. What should I do next?