The problem involves a collision between two runners, where one runner's mass is known, and the goal is to determine the mass of the second runner based on the principle of momentum conservation. The scenario describes both runners coming to a complete stop after colliding.
The discussion is active, with participants affirming the importance of momentum conservation. Some have provided insights into the relationship between mass and velocity in the context of the problem, while others are questioning the assumptions regarding the nature of the collision.
There is a lack of specific equations mentioned by the original poster, and some participants are exploring the implications of the runners' masses and velocities in relation to the collision outcome.
sean-820 said:I think that's right. If one was 200lbs then that one would blow through the other guy and not stop at the point of collision like i think the question is saying.
Right.javas1 said:Yes, it is momentum, I believe.
They may or may not bounce off, but no matter what, momentum will be conserved. Here you are told that they come to a stop, so you know they don't bounce off.I read that if two objects crash into each other, then they bounce off each other - and that is not a complete stop.
Yes, exactly right. Since they come to a complete stop, you know that the total momentum is zero. That can only be true if their initial momenta are equal and opposite. Since they have the same speed, the only way they can have the same momentum is if they have the same mass.However, it seems that the mass of both objects would need to be equal, as long as the velocity is equal.
Is that right?
Doc Al said:Right.
They may or may not bounce off, but no matter what, momentum will be conserved. Here you are told that they come to a stop, so you know they don't bounce off.
Yes, exactly right. Since they come to a complete stop, you know that the total momentum is zero. That can only be true if their initial momenta are equal and opposite. Since they have the same speed, the only way they can have the same momentum is if they have the same mass.