Is Ignoring the Y-Component in Billiard Ball Collision Calculations Correct?

AI Thread Summary
The discussion revolves around the calculation of the original speed of a cue ball after a collision with a stationary billiard ball. The user expresses uncertainty about their solution, particularly regarding the omission of the y-component of velocity, specifically 1.2sin30 degrees. They seek clarification on whether this component is necessary for an accurate solution and how it should be incorporated. The problem involves applying the principle of conservation of momentum, and the user is looking for guidance on the direction of the second ball post-collision. Understanding the role of both x and y components in collision calculations is crucial for accurate results.
aatari
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Could someone please have a look at my solution and tell me if it makes sense. Although I am able to get the initial velocity that the question asked for, however the fact that I did not incorporate the y-component which is 1.2sin30 degrees into the solution makes me doubtful. If I do need to use that into the solution, how would that fit in? Please help!

1. Homework Statement


A 0.50 kg cue ball makes a glancing blow to a stationary 0.50 kg billiard ball. After the collision the cue ball deflects with a speed of 1.2 m/s at an angle of 30.0° from its original path. Calculate the original speed of the cue ball if the billiard ball ends up traveling at 1.6 m/s.

Homework Equations



Pi = Pf

The Attempt at a Solution


20171014_232649[43448].jpg


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aatari said:
Could someone please have a look at my solution and tell me if it makes sense. Although I am able to get the initial velocity that the question asked for, however the fact that I did not incorporate the y-component which is 1.2sin30 degrees into the solution makes me doubtful. If I do need to use that into the solution, how would that fit in? Please help!

1. Homework Statement


A 0.50 kg cue ball makes a glancing blow to a stationary 0.50 kg billiard ball. After the collision the cue ball deflects with a speed of 1.2 m/s at an angle of 30.0° from its original path. Calculate the original speed of the cue ball if the billiard ball ends up traveling at 1.6 m/s.

Homework Equations



Pi = Pf

The Attempt at a Solution


View attachment 213143
[/B]
In what direction do you think the second ball will go?
 
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