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Homework Help: Simple pendulum oscillation

  1. May 28, 2003 #1

    Dx

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    Hello,

    I have two test questions that I missed AT school so i wrote them down. I wanted to know the correct answers as well as a short description of how they came up with that.

    1) a simple pendulum consists of a mass attached to a weightless string L. For this system when undergoing small oscillation

    a. frequency proportional to amplitude -->that was my original answer
    b. period proportional to amplitude
    c. frequency independent of mass
    frequency is independent of length

    My new answer from what I read and understand would be d, am i correct?

    2) Simple pendulum A swings back n forth at twice the frequency of a simple pendulum B. what statement is correct?

    a. B is twice as long as A
    b. B is twice as massive as A
    c the length of B is 4 times the length of A
    d. the mass of B is 4 times the mass of A

    i dont remember but i think the formula is 1/2pi * sqrt(g/L)
    anyways can anyone tell me the correct answer and briefly why?

    Thanks!
    Dx
     
  2. jcsd
  3. May 28, 2003 #2

    Tom Mattson

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    Staff Emeritus
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    Dx, just look up the formulas for the frequency of a physical pendulum. That tells the whole story for #1. As for #2, you got the formula right, so use it to get the answer.

    fA=(1/2π)(g/LA)1/2
    fB=(1/2π)(g/LB)1/2

    You are told that fA=2fB

    Can you take it from there?
     
  4. May 28, 2003 #3

    Dx

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    Okay!

    Ill take it tom. ill let you know how it went, k
    Thanks!
    dx :wink:
     
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