Momentum Question: Calculating X & Y Component After Collision

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Homework Help Overview

The discussion revolves around a momentum problem involving a collision between two pool balls. The original poster describes a scenario where a moving white ball strikes a stationary black ball, with given masses and initial velocities but lacking specific angles or velocities post-collision.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants explore the application of conservation of momentum and question the adequacy of the provided information. Some suggest expressing the answer in terms of the unknown values, while others discuss potential angles involved in the collision.

Discussion Status

The discussion is ongoing, with participants offering various insights and questioning the assumptions made about the angles and values involved. There is no explicit consensus, but some guidance on applying conservation of momentum has been suggested.

Contextual Notes

Participants note the absence of specific angles and velocities in the problem, raising concerns about whether the question is flawed or incomplete.

riley_5000
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Hi Everyone

I would really appreciate some help with a momentum question; I don't want the whole answer, just the first step would be great!

I have attached the diagram. A white pool ball is rolling along the pool table and strikes a stationary black ball. The white ball's initial mass and velocity is given (black ball's mass is the same), so initial system momentum is simple.

The question wants the x and y momentum components for each ball after collision. But no further angles / velocities are given (angles are not 45 deg) and diagram given is not to scale - so I don't even know where to start!

The previous question at least gave one angle and one velocity,so that was simple enough. Is the question flawed, or can someone please assist me just to get started - then I can finish the rest myself?
 

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Is this problem from your textbook?
 
Perhaps the answer is expected to be expressed in terms of the missing values. That's the best you can do with the given information.
 
Have you applied conservation of momentum to this problem?
 
I think SteamKing is correct. Momentum of each ball after collision is half of momentum of white ball before the collision. Then use trig to calc x,y components.

Why do you think the angles are not 45 degrees? Is that what the textbook says?
 
Hi All

I'm working through problems in preparation for the exams. The after collision individual momentums are are not half of the starting value, and the angles (from memory - I'm not at home) were around 53 deg for the white and I can't remember the black.

I'm beginning to wonder if there isn't a value missing in the text question.
 

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