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Two balls, A and B, having different but unknown masses, collide. A is initially at rest and B has a speed v. After collision, B has a speed v/2 and moves at right angles to its original motion.
a) Find the direction in which ball A moves after the collision.
b) Can you determine the speed of A from the information given? Explain
So, conversation of momentum
lets let ball A have mass m, and ball B have mass M
mVai + Mvi = mVaf + Mvf
0 + Mv = mVaf + (1/2)Mv
(1/2)Mv = mVaf
Vaf = (Mv)/2m
It seems I need to solve B before solving A
Since ball B moves at a right angle to its initial velocity, if we say it was moving only in the x direction initally, it now has no x coordinate of velocity, so all of its x momentum will be transferred to ball A
so cosx = v/[(Mv)/2m]
cosx = 2mv/Mv
cosx = 2m/M
x = arccos(2m/M)
Have I done all of this right?
Thanks
a) Find the direction in which ball A moves after the collision.
b) Can you determine the speed of A from the information given? Explain
So, conversation of momentum
lets let ball A have mass m, and ball B have mass M
mVai + Mvi = mVaf + Mvf
0 + Mv = mVaf + (1/2)Mv
(1/2)Mv = mVaf
Vaf = (Mv)/2m
It seems I need to solve B before solving A
Since ball B moves at a right angle to its initial velocity, if we say it was moving only in the x direction initally, it now has no x coordinate of velocity, so all of its x momentum will be transferred to ball A
so cosx = v/[(Mv)/2m]
cosx = 2mv/Mv
cosx = 2m/M
x = arccos(2m/M)
Have I done all of this right?
Thanks