. A blue lab cart is traveling west on a track when it collides with and sticks to a red lab cart traveling east. The magnitude of the momentum of the blue cart before the collision is 2.0 kilogram • meters per second, and the magnitude of the momentum of the red cart before the collision is 3.0 kilogram • meters per second. The magnitude of the total momentum of the two carts after the collision is a. 1.0 kg • m/s b. 2.0 kg • m/s c. 3.0 kg • m/s d. 5.0 kg • m/s
The total momentum before the collision is the sum of the momenta of the blue and the red cart:
Total momentum before = momentum of blue cart + momentum of red cart
Total momentum before = 2.0 kg • m/s + 3.0 kg • m/s
Total momentum before = 5.0 kg • m/s
Since momentum is conserved in collisions, the total momentum after the collision is also 5.0 kg • m/s. Therefore, the correct answer is:
d. 5.0 kg • m/s