MHB Proving Perpendicular Motion: 2 Masses Colliding Obliquely

AI Thread Summary
In the discussion on proving perpendicular motion during the oblique collision of two spheres, the conservation of momentum is applied to establish the relationship between their velocities before impact. The equations derived include 4x + 2y = 4p, where x and y represent the initial velocities of the 2kg and 4kg masses, respectively, and p is the velocity of the 4kg mass after impact. The coefficient of restitution, set at 1/2, is used to relate the velocities before and after the collision through Newton's experimental law. Participants express confusion about how to proceed once the velocities are expressed in terms of unknown variables. The discussion emphasizes the importance of understanding the momentum conservation principle in analyzing the collision dynamics.
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two smooth spheres of masses 2kg and 4kg collide obliquely . the 2 kg mass is brought to rest. the coefficient of restitution is 1/2
prove before the impact the spheres were moving in perpendicular directions to each other.

using conservation of momentum. 4x+2y=4p+2(0) where x and y are velocities before impact. p is velocity after impact of 4kg

Newtons experimental law p-0/x-y =-1/2

once i get there velocities in terms of the variables i don't know what to do
 
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the velocity in the j direction does not change as its along the i axis
 
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