Question

Two identical freight cars roll without friction (one at 1 m/s, the other at 2 m/s) toward each other on a level track. They collide, couple together, and roll away in the direction that _________.

Answer 1

In a collision between two objects, such as the freight cars described in the question, the momentum of the system is conserved. The two joined carts will roll away in the direction of the car with the greater initial velocity (-2 m/s).

Step-by-step explanation:

In a collision between two objects, such as the freight cars described in the question, the momentum of the system is conserved. Momentum is the product of an object's mass and its velocity, and it is a vector quantity.

When the two freight cars collide, they couple together and roll away with a common final velocity.

In this case, the momentum of the system before the collision is the sum of the momentum of each car, and it must be equal to the momentum of the system after the collision.

Therefore, the direction of the final velocity of the two joined cars will depend on the magnitudes and directions of their initial velocities. Since one of the cars is moving to the left (-2 m/s) and the other is moving to the right (1 m/s), their final velocity will be determined by the algebraic sum of their initial velocities.

So the final velocity of the two joined cars will be to the direction of the car with the greater initial velocity (-2 m/s).