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PHY 201
Your 'cq_1_24.2' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** CQ_1_24.2_labelMessages **
A steel ball of mass 60 grams, moving at 80 cm / sec, collides with a stationary marble of mass 20 grams. As a result of the collision the steel ball slows to 50 cm / sec and the marble speeds up to 70 cm / sec.
• Is the total momentum of the system after collision the same as the total momentum before?
answer/question/discussion: ->->->->->->->->->->->-> :
mAvA + mBvB = mAv'A + mAv'B
.06kg(.8 m/s) + .02kg(0 m/s) = .06kg(.5 m/s) + .02kg(.7 m/s)
.048 kg*m/s + 0 kg*m/s = .03 kg*m/s + .014 kg*m/s
.048 kg*m/s > .044 kg*m/s
The total momentum of the system after the collision is NOT the same as the momentum before.
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• What would the marble velocity have to be in order to exactly conserve momentum, assuming the steel ball's velocities to be accurate?
answer/question/discussion: ->->->->->->->->->->->-> :
.048 kg*m/s = .03kg*m/s + .02kg(v'B)
.018 kg*m/s = .02kg(v'B)
v'B = 90 cm/s
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7 mins
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&#Very good responses. Let me know if you have questions. &#