Question

A railroad car with a mass of 90,000 kg is traveling along a straight, horizontal track at a constant speed of 2 m/s. the car collides with a second railroad car, also with a of 90,000 kg that is initially at rest. The railroad cars stick together after the collision, as shown in the figure.

1) 0.5 m/s
2) 1 m/s
3) 2 m/s
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Answer 1

Using the conservation of momentum, the final velocity of two identical railroad cars sticking together after collision is calculated to be 1 m/s.

Step-by-step explanation:

The question asks about the final velocity of two railroad cars that collide and stick together. This is a classic physics problem involving the conservation of momentum. To find the final velocity, we use the law of conservation of momentum which states that the total momentum of a closed system is conserved if there is no external force acting on it.

Since the two cars stick together after the collision, we can calculate the final velocity (vf) using the formula: (m1 x v1 + m2 x v2) / (m1 + m2), where m1 and m2 are the masses of the cars, and v1 and v2 are their initial velocities. In this case, m1 = m2 = 90,000 kg, v1 = 2 m/s and v2 = 0 m/s (since the second car is initially at rest).

After the collision, the combined mass is m1 + m2 = 180,000 kg, and the combined momentum is m1 x v1 = 180,000 kg x 2 m/s = 180,000 kg-m/s. Thus, the final velocity is:

vf = (180,000 kg-m/s) / (180,000 kg) = 1 m/s

The cars will move together with a final velocity of 1 m/s after the collision.

Answer 2

I think it's 2.

Step-by-step explanation:

The weight should transfer half of it's velocity to the other one. or its 1