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Homework Help: Few homework questions

  1. Feb 13, 2005 #1
    I'm having some trouble with a few rotational motion problems.

    One question says... A wheel 33 cm in diameter accelerates uniformly from 240 rpm to 360 rpm in 6.5 s. How far will a point on the edge of the wheel travel in this time.

    Is this asking for the angular displacement or the linear displacement?

    The next one says A bowling ball of mass 7.3 kg rolls without slipping down a lane at 3.3m/s. (a) calculate its total kinetic energy. (b) Calculate its angular momentum

    I can see how to get the total kinetic energy i think, but how do i find the angular momentum if i dont have the radius or the angular velocity?

    Any help would be appreciated
     
  2. jcsd
  3. Feb 13, 2005 #2

    dextercioby

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    1.There's no linear movement,therefore u should compute the length of the circle the point travels in that time.
    2.As for the last,i may be wrong,but you need the radius...

    Daniel.
     
  4. Feb 14, 2005 #3

    BobG

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    The radius of a bowling ball is common knowledge and shouldn't need to be put into the problem. Virtually everybody knows that the radius of a bowling ball is 10.85 cm (plus or minus .05 cm).

    Most people do know that, right? :uhh:

    BTW, a 7.3 kg bowling ball isn't legal - it's about 44 grams too heavy. Check here for all you want to know about a bowling ball: http://www.bowl.com/downloads/pdf/USBCequipmanual2005_sectionIII.pdf" [Broken]
     
    Last edited by a moderator: May 1, 2017
  5. Feb 14, 2005 #4

    dextercioby

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    Nope,Bob,i never did and never will play bowling.:tongue:

    Daniel.
     
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