Rank the velocities of the balls

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The discussion revolves around ranking the final velocities of various masses in an elastic collision scenario. Participants emphasize the importance of the conservation of momentum, noting that the total momentum of the system must remain zero before and after the collision. There is confusion regarding why the heaviest mass does not necessarily have the highest final velocity, with explanations suggesting that lighter masses are more easily influenced during collisions. The conversation highlights the need to apply generic equations for elastic collisions to analyze the outcomes effectively. Understanding these principles is crucial for solving the problem accurately.
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Homework Statement

Small masses m1 (m1 = 30 kg) and m2 (m2A = 5 kg; m2B = 10 kg; m2C = 40 kg; m2D = 50 kg; m2E = 30 kg) are each attached to a string of length 2.0 m. The other end of each string is attached to a common point on the ceiling. The masses are raised until each string is at an angle of 22o with respect to vertical, and then simultaneously released. They collide elastically when the strings are vertical. For each case, rank the final velocity of m2, from smallest to largest.

Homework Equations

using the elastic equation formula



The Attempt at a Solution

i don't understand y the heaviest one wouldn't be going the fastest...
 
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You just need to write generic equations for an elastic collision and then plug in the masses for each case.
 
The heaviest one is the one most difficult to influence - whereas the lightest one is the easiest. Or what happens if you roll 2 marbles of different weights together?

I think this assignment has to do with the law of conservation of momentum.

If you release all the balls at an angle, by the time they're about to collide, the system has a total momentum of 0, and after the collision has happened it will need to stay that way.
 
oh ok I see that analogy explains it better...i will work on that and see what I get. thanks
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...

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