1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    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!

Standing waves

  1. Jun 14, 2009 #1
    1. The problem statement, all variables and given/known data
    What is the longest wavelength for standing waves on a 254.0 cm long string that is fixed at both ends?

    2. Relevant equations

    3. The attempt at a solution
    When x = L (length of string):

    k(n) = n*pi / L
    wavelength (n) = n*pi / k(n)

    I got the answer, I just don't understand why these equations are used in my textbook to find this particular answer.
    Last edited: Jun 14, 2009
  2. jcsd
  3. Jun 14, 2009 #2


    User Avatar
    Homework Helper

    "how can a wave be made?"

    Imagine pulling on the rope hard, to make it taut. You could then make the rope vibrate like a guitar string.

    A wave has to be set up in the rope to make it vibrate. Obviously, the fixed ends can't be vibrating, which sets restrictions on the permitted wavelengths. So: what's the longest possible wavelength?
  4. Jun 14, 2009 #3


    User Avatar
    Homework Helper

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Standing waves Date
Error calculation for µ in standing wave experiment Feb 20, 2018
Mass of a vibrating string Nov 24, 2017
Resonating wineglass problem Nov 3, 2017