cq_1_242

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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.

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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: ->->->->->->->->->->->-> :

We need to use the formula: m1v1+m2v2= m1’v1’+m2’v2’

60g(80cm/s)+ 20g(0)= 60g(50cm/s)+ 20g(70cm/s)

4800+0=4400

No, the momentum is not the same.

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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: ->->->->->->->->->->->-> :

The momentum of the marble would have to be 90cm/s to equal the momentum.

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10 minutes

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Very good.