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: SHM/Pendulum prob

  1. Feb 23, 2010 #1
    1. The problem statement, all variables and given/known data
    I'm stuck on the last 2 parts of this problem and would really appreciate any help!

    A pendulum of length 2m and mass 1kg oscillates about its equilibrium position. At time 1s it has a displacement of 20cm. Assume that (phi symbol) = 0 rad.

    2. Relevant equations

    a) Its angular velocity

    b) the frequency of oscilation

    c) the amplitude

    d) the maximum angle from the verticle made by the pendulum

    e) the speed of the pendulum is given by v(t) = w(ang. vel)A(amplitude)cos(wt+phi). Calculate the kinetic energy at positions theta = 0 rad and theta = 1/2 pi rad

    f) where on the pendulum's cycle do these energies occur and why are they different?

    3. The attempt at a solution
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Feb 23, 2010 #2


    User Avatar
    Homework Helper

    You need to show some sort of attempt. If it moves with SHM, what is the general form of its motion? x(t) = ?
  4. Feb 24, 2010 #3
    These are the answers I got:

    A) 2.21 ms^-1

    B) 0.35Hz

    C) 0.25m

    D) 0.13 rads

    E) ?

    F) ?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook