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Homework Help: So, we're playing snooker

  1. Feb 7, 2010 #1
    So, we're playing snooker....

    1. The problem statement, all variables and given/known data

    A (uniform) snooker ball of radius r, at rest on a table, is struck by a cue at a point a distance h above the table. Assume the cue tip is travelling horizontally, in a plane through the centre of the ball. As a result, the ball begins to move with an initial linear speed V0 and angular speed w0.

    Consider the cue as acting with a large force F for a short time. Ignoring the effects of friction between the ball and the table for this time, find an expression for the ratio V0/w0 in terms of h.

    2. Relevant equations

    Once I've sussed the question, I can identify which.

    3. The attempt at a solution

    Well, I'm confused due to the sentence; "Assume the cue tip is travelling horizontally, in a plane through the centre of the ball". This to me means, that h = r? Therefore, if friction is to be ignored this time, the ball will not (initially) rotate?

    If someone could clear this up, I'm sure I can crack on with the next few parts of the question.
     
  2. jcsd
  3. Feb 7, 2010 #2

    Doc Al

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    Staff: Mentor

    Re: So, we're playing snooker....

    I suspect that it's just a sloppily worded problem, and that the 'in a plane through the center of the ball' should be ignored. (Otherwise your interpretation is correct, but then the problem makes little sense.)

    (This isn't from some textbook, I hope. If it is, give a reference.)
     
  4. Feb 7, 2010 #3
    Re: So, we're playing snooker....

    I would assume it means in a vertical plane through the centre of the ball. In other words, you are not putting any side spin on it.
     
  5. Feb 7, 2010 #4

    Doc Al

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    Staff: Mentor

    Re: So, we're playing snooker....

    Excellent. That's it.
     
  6. Feb 7, 2010 #5
    Re: So, we're playing snooker....

    Probably, my Mechanics Lecturer isn't the greatest at writing them.

    Awesome, I'll try it like that. Thanks!
     
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