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!

Bullet shot into pendulum - conservation of energy

  1. Oct 13, 2008 #1
    1. The problem statement, all variables and given/known data
    A 27-g rifle bullet traveling 230m/s buries itself in a 3.3-kg pendulum hanging on a 2.9-m-long string, which makes the pendulum swing upward in an arc.
    Determine the vertical and horizontal components of the pendulum's maximum displacement.
    x=? and h=?

    2. Relevant equations
    v= (m+M)/m * sqr root (2gh)

    3. The attempt at a solution
    I just expanded on the above equation and derived several others ..dont know where to go next.. L = length of string ; M=block's mass ; h=max height ; x=distance on x axis ; m=bullet's mass
    v= (m+M)/m * sqr root (2gh)
    (v* (m/m+M)^2)/(2g)=h
    h= L(1-cos theta)
    cos-1 theta(-1 ((h/L)-1) = theta
    L sin theta = x
    EDIT: sorry nicksauce. I have now included the question.
    Last edited: Oct 13, 2008
  2. jcsd
  3. Oct 13, 2008 #2


    User Avatar
    Science Advisor
    Homework Helper

    Re: pendelum

    What exactly is the question here? I see no question marks in your post.
  4. Oct 14, 2008 #3


    User Avatar
    Staff Emeritus
    Science Advisor

    Re: pendelum

    I would be inclined to use "conservation of Energy". You can calculate the kinetic energy of the bullet and you can take the potential energy to be 0 at the bottom of the arc. At the highest point the kinetic energy of both is 0 so all energy has be changed to potential energy. From the potential energy you can find the height.

    I think this will get a better response in the physics section so I am going to move it there.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Bullet shot into pendulum - conservation of energy
  1. Bullet and Pendulum (Replies: 5)