A magnetic hockey puck (0.40 kg) hits another hockey puck (0.40 kg) at rest and both travel together to the right at 8.0 m/s. How fast was the first hockey puck initially moving?

Question

anonymous · Answer

This question has to do with conservation of momentum so consider the "system" as containing the 2 hockey pucks so the sum(momentum initial) = sum(momentum final). The for the initial momentum you have to consider the mass*velocity of each of the two pucks whereas for the final you have to treat them as one particle. Essentially M1V1 +M2V2 = (M2+M1)V3 and you hve to solve for V1