Object 1, which has mass 100 kg, is moving at 3 m/s and collides with Object 2, which has mass 50 kg and is moving at -8 m/s. If the first object stops moving after the collision, how fast would the second object be moving at that time?
I think the answer is -2 m/s.
momentum conservation
initial=final
100*3+50*(-8)=100*0 + 50*V
I agree with your answer.
To find the final velocity of Object 2 after the collision, we can use the principle of conservation of momentum.
The momentum of an object is defined as the product of its mass and velocity. The principle of conservation of momentum states that the total momentum of a closed system remains constant before and after a collision.
In this case, the closed system consists of Object 1 and Object 2.
Before the collision, the total momentum of the system is given by:
Total momentum before = (mass of Object 1 * velocity of Object 1) + (mass of Object 2 * velocity of Object 2)
Let's calculate the initial momentum of the system:
Total momentum before = (100 kg * 3 m/s) + (50 kg * (-8 m/s))
Total momentum before = 300 kg·m/s - 400 kg·m/s
Total momentum before = -100 kg·m/s
Since the system is closed and there are no external forces acting on it, the total momentum after the collision will also be -100 kg·m/s.
After the collision, Object 1 stops moving, so its final velocity is 0 m/s.
Let's denote the final velocity of Object 2 as v2 (to be determined).
The total momentum after the collision is given by:
Total momentum after = (mass of Object 1 * final velocity of Object 1) + (mass of Object 2 * final velocity of Object 2)
Since the final velocity of Object 1 is 0 m/s, we can simplify the equation to:
Total momentum after = (mass of Object 2 * final velocity of Object 2)
Equating the total momentum after the collision to the initial momentum, we have:
-100 kg·m/s = 0 kg * 0 m/s + 50 kg * final velocity of Object 2
Solving for the final velocity of Object 2:
final velocity of Object 2 = (-100 kg·m/s) / (50 kg)
final velocity of Object 2 = -2 m/s
Therefore, the second object would be moving at -2 m/s after the collision. Your answer of -2 m/s is correct!