A string is stretched between two supports that are L = 1.2 m apart. It resonates at a frequency of f = 450 Hz with a standing wave pattern that has two nodes between the two supports.(adsbygoogle = window.adsbygoogle || []).push({});

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(a)Using the unit of m , find the wavelength l.

Wavelength = .8

I did 1.2*2 /3 which is the correct answer then

(b) Suppose that the tension, T, in the string is increased by a factor of 4. What is the new frequency, f', in unit of Hz , if the string vibrates with the same standing wave pattern that it began with (i.e. A standing wave pattern that has two nodes between the supports).

HELP: The wave length l is determined by the number of nodes, so it keeps unchanged; however, the wave speed is determined by the tension T and the string's density d = mstring/L, so it will change.

HELP: First, find the incresing factor of the wave speed v by using the equation of v2 = T/d, and then find the incresing factor of the frequency by using the equation of v = f l. Remember, l = l' because the number of nodes is same.

I dont know what the mass of the string is so how do i find it inorder to get desity? Thanks

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# Homework Help: String Stuff

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