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Introduction
Physics teachers who are either writing physics questions that deal with waves on a string, or setting up equipment for a class lab or demo of standing waves on a string, might find the following analysis useful. When writing questions for physics tests or homework, it is preferable to use physically plausible values for any quantities (Ref. 1). With that in mind, let us explore what physically limits quantities such as wave speed or string tension in a typical standing-wave setup for a school physics lab.

The above figure shows a typical standing-wave setup. An oscillator at one end of a string vibrates vertically to produce waves along the string, while the weight hanging at the other end holds the string taut. A pulley confines the waves to the horizontal section of the string while still allowing the force exerted by the weight to hold the string taught.
The...

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Drakkith, berkeman, BvU and 5 others

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I'm particularly interested in hearing from physics teachers or students who have used these setups, especially if your setup was outside what I'm calling the "physically reasonable zone".

sophiecentaur
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if your setup was outside what I'm calling the "physically reasonable zone".
I'm not sure what you mean by that expression, exactly but I have used an alternative method which might interest you. The method involves electromagnetic force. A nice beefy horseshoe magnet is placed with a stretched steel wire held between the poles. One end is fixed and the other is tensioned with a variable mass. A fairly powerful signal generator is connected across the ends of the wire. Not directly on the wire but to the fixing and pulley so that the excitation is 'clean' and can be applied at any point along the wire. I prefer this method because, unlike when the end of the string is moved, the precise wavelength can be measured because true Nodes can be seen at each end.
Good magnets are easily obtainable these days - much better ones than what I had available a few years ago and a standard School Oscillator will give you frequencies from a few Hz to a few tens of Hz.
Give it a go.

Redbelly98 and vanhees71
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Oh, cool setup!
I'm not sure what you mean by that expression ...
I was referring to the two diagrams toward the of the article -- to see them, you'd need to click the "Continue reading" link. (Not sure if you didn't see the diagrams, or did see them and something still isn't clear about them.)

sophiecentaur