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!

Homework Help: Potential Energy and Conservation Energy.

  1. Jul 27, 2009 #1
    1. The problem statement, all variables and given/known data

    Suppose the pendulum bob in the figure has a mass of 0.33 Kg and is moving to the right at point B with a speed of 2.4 m/s . Air resistance is negligible.

    The diagram is given here :
    http://session.masteringphysics.com/prob… [Broken]

    I calculated the bob's kinetic energy at point B which is 0.95 J.

    Can anyone help me out with following two questions?

    At some point the bob will come to rest momentarily. Without doing an additional calculation, determine the change in the system's gravitational potential energy between point B and the point where the bob comes to rest.

    I got 0.95 J for the potential Energy for this..

    1. Find the maximum angle the string makes with the vertical as the bob swings back and forth. Ignore air resistance.

    2. Relevant equations

    Kinetic Energy = 1/2 mv^2
    Potential Energy is = mgh

    3. The attempt at a solution

    The bob comes to momentary rest at point A which has largest P.E.
    For the first question, I think I have to find P.E between point A and B. So I solved it now and got it right...

    Second question.. I am completely clueless.. Can anyone please give me any hints???

    Can anyone please explain it and help me out?

    Thanks a lot before hand!

    I solved the whole thing
    Last edited by a moderator: May 4, 2017
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted