1. The problem statement, all variables and given/known data An object with mass m and an object with mass 3m collide in one dimension. The object with mass m is moving at 3 times the velocity of the object with mass 3m. What can you say about their velocities after the collision? 2. Relevant equations m1vi1 + m2vi2 = m1vf1 + m2vf2 3. The attempt at a solution Well first I tried to use the equation for conservation of momentum and solve for the final velocities but it got quite messy and I wasn't getting anywhere. But if they collide head on wouldn't the velocities after the collision have to be 0 since the total momentum before would be 0? The only thing is it doesn't say theyre colliding head on.