1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Kinetic Energy of a Bowling Ball

  1. Mar 22, 2012 #1
    1. The problem statement, all variables and given/known data

    A bowling ball of mass 7.2 kg and radius 9.1 cm rolls without slipping down a lane at 3.0 m/s.

    What is the total kinetic energy of the bowling ball?

    2. Relevant equations
    KE rot. = 1/2 Iω^2

    3. The attempt at a solution

    KE initial = 0 J (I'm assuming it started from rest).
    I = 2/5 (7.2 kg)(0.091 m)^2
    I = 0.0238492 kg * m^2
    I used the formula for a uniform sphere to calculate this.

    3.0 m/s / 0.091 m = 0.3296 rad./s

    KE final = 1/2 (0.0238492 kg*m^2)(0.3296 rad./s)^2
    KE final = 1.3 * 10 ^ -3 J

    I'm thinking I messed up at the "I" variable because my answer is tiny.
     
    Last edited: Mar 22, 2012
  2. jcsd
  3. Mar 22, 2012 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Recheck this calculation.

    Also: Don't forget the translational KE.
     
  4. Mar 22, 2012 #3
    DocAl - I redid the calculation and read the exponent of 3.296 as -1 and not +1. I added in the translational kinetic energy and got the right answer of 45 J.
     
  5. Mar 22, 2012 #4

    Doc Al

    User Avatar

    Staff: Mentor

    Good!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Kinetic Energy of a Bowling Ball
  1. Bowling Ball (Replies: 1)

Loading...