Momentum Question: Calculating X & Y Component After Collision

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The discussion revolves around a momentum problem involving a collision between a moving white pool ball and a stationary black ball, with both having the same mass. Participants express confusion over the lack of specific angles and velocities after the collision, making it difficult to calculate the x and y momentum components. One contributor suggests that the momentum of each ball post-collision is half of the white ball's initial momentum, while another questions the assumption that the angles are not 45 degrees. There is speculation about whether the problem is flawed or missing crucial information. The conversation emphasizes the importance of applying conservation of momentum principles to solve the problem.
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.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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