Collision of Two Particles: Elastic Momentum Transfer Formula | Help Needed

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The discussion focuses on deriving the formula for momentum transfer during an elastic collision between two particles with masses m1 and m2. The user seeks help in proving that the momentum transferred from the first particle to the second can be expressed as 2m1*m2(u - v)/(m1 + m2). The conservation of linear momentum and kinetic energy in elastic collisions is emphasized as a key principle. After working through the equations, the user successfully arrives at the desired formula, confirming the solution. The thread concludes with appreciation for the assistance received.
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transfer of momentum...help needed ?

Homework Statement



two particles of masses m1 & m2 are moving along a straight line with velocities u & v respectively. they collide to each other..if the collision between them is an elastic collision then show that momentum transferred from first particle to second particle is 2m1*m2(u - v)/m1 + m2...


Homework Equations



I am trying to use the condition of an elastic collision...their linear momentum & kinetic energy will be conserved..but the proof is not coming out...please help me with it...

if the velocity of first particle after collision is u1 & the same of the 2nd particle is v1 then we know, u1 = (m1 - m2)*u/(m1 + m2) + 2m2*v/(m1 + m2)

v1 = 2m1*u/(m1 + m2) - (m1 - m2)*v/(m1 + m2)

The Attempt at a Solution


 
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Show your work.

ehild
 


v1 = 2m1*u/(m1 +m2) - (m1 - m2)*v/(m1+m2)

momentum of the 2nd particle after collision

m2v1 = 2m1*m2*u/(m1+m2) - (m1-m2)*m2*v/(m1+m2)

transfer of momemtum

m2v1 - m2v = 2m1*m2*u/(m1+m2) - (m1-m2)*m2*v/(m1+m2) - m2v

[2m1*m2*u - (m1-m2)*m2*v - (m1+m2)*m2v]/(m1+m2)

[2m1*m2*u - (m1-m2)*m2*v - m1*m2*v - m2^2v]/(m1+m2)

[2m1*m2*u - m1*m2v + m2^2v - m1*m2*v - m2^2v]/(m1+m2)

[2m1*m2*u - 2m1*m2*v]/(m1+m2)

2m1*m2(u-v)/(m1+m2)


it is sloved

BTW thanks
 


Good job!

ehild
 
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