Question

Now consider the collision represented in the animation below. Let's assume that the two balls are sliding on a frictionless, horizontal surface. Do not assume that this collision is elastic (though it might be). Here's what's given:

The direction of +x is to the right.The blue ball has twice the mass of the red. Let's make them mb = 2 kg and mr = 1 kg.

The red ball is initially stationary.

The initial velocity of the blue ball, vbi, is 6 m/s, and its final velocity, vbf, is 2 m/s.

1)Find the final velocity, vrf, of the red ball, in meters per second. Enter only a single number (without units) before submitting. If your answer isn't an integer, you've made a mistake somewhere ! 2)The principle that I used to get the answer to the previous question was conservation of ... 3)

the initial KE of the system (both balls) in this problem is: (give answer and show/explain how you got it) 4)

The final KE of the system (both balls) in this problem is: (give answer and show/explain how you got it) 5) was the collision elastic?

Answer 1

Mass of red ball .m_r =1kg

Initial velocity of red ball ,v_ri =0m/s

Mass of blue ball .m_b =2kg

Initial velocity of blue ball ,v_bi =6m/s

Final velocity of blue ball ,v_bf =2m/s

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Momentum is conserved

Momentum before collision =Momentum after Collision

(1) ANSWER: 8

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(2) ANSWER: Momentum

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(3) Initial Kinetic Energy ,

ANSWER:

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(4) Final Kinetic Energy ,

ANSWER:

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(5) Initial Kinetic energy is equal to final kinetic energy

so Kinetic enrgy is conserved

ANSWER: Yes,Collision was elastic

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