1. Not finding help here? Sign up for a free 30min 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!

A Rolling Bat Struck by a Ball

  1. Oct 9, 2013 #1
    A bat lies along the x-axis so that the tip of its handle is located in (0, 0) while the other end is at (0.9 m; 0). The center of mass is at (0.6 m; 0). A ball hits the bat perpendicularly at (x, 0), causing an impulse I.
    The bat’s moment of inertia through the center of mass is J = 0.0530 kgm^2; the bat’s mass m = 0.800 kg.
    Calculate x so that the tip of the handle stays at (0, 0) by studying the movement of the center of mass.

    I assumed that the axis is parallel with z-axis and that the bat starts rolling around the point (0, 0). I calculated J about the tip of the handle. After that, however, I am stuck since I can only form equations with several unknown variables. Also, I don’t really understand the conditions under which the tip of the handle remains at (0, 0). Have I approached the assignment incorrectly or am I missing something (or both)?

    All help is much appreciated.
     
  2. jcsd
  3. Oct 9, 2013 #2

    collinsmark

    User Avatar
    Homework Helper
    Gold Member

    I think the problem is asking for the distance x, such that the bat handle's tip's instantaneous velocity is zero, immediately after the impulse.

    I can guarantee you that the tip of the handle will not stay stay at (0, 0) indefinitely, without other forces involved holding it in place. But its initial, instantaneous velocity can be zero so long as the x is just right. I think that's what you are being asked to calculate.

    [Hint: you need to figure out the situation that the rotation movement of the tip, [STRIKE]ωx[/STRIKE] [Edit: I meant ωxc, where xc is the distance from the center of mass to the handle's tip, not to be confused with x, the distance from the tip to the location of the ball striking] is equal and opposite v, the velocity of the center of mass.]
     
    Last edited: Oct 9, 2013
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: A Rolling Bat Struck by a Ball
  1. Force of bat on ball (Replies: 1)

  2. Bat hitting a Ball (Replies: 11)

Loading...