## Questions 20-21
Two pucks moving on a frictionless air table are about to collide, as shown above. The 1.5 kg puck is moving directly east at 2.0m/s. The 4.0 kg puck is moving directly north at 1.0m/s.
21. What is the magnitude of the total momentum of the two-puck system after the collision?
(A) 1.0kg⋅m/s
(B) 3.5kg⋅m/s
(C) 5.0kg⋅m/s
(D) 7.0kg⋅m/s
(E) 5.55kg⋅m/s