Calculating Mass Using Standing Waves on a Suspended Wire

AI Thread Summary
The problem involves calculating the mass M attached to a wire based on changes in frequency due to added weight. The second-harmonic frequency increases from 200 Hz to 245 Hz when an additional 1 kg is added. The relevant equations include the frequency formula f = v/L and the wave speed v = √(T/u), where T is tension and u is mass per unit length. The user attempted to solve the problem by substituting values into the equations but expressed uncertainty about the correctness of their approach. The discussion highlights the need for clarity in applying physics principles to solve for the unknown mass M.
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Homework Statement


When mass M is tied to the bottom of a long, thin wire suspended from the ceiling, the wire's second-harmonic frequency is 200 Hz. Adding an additional 1kg to the hanging mass increases the second-harmonic frequency to 245 Hz. What is M?
f_{2} = 200hz, m = M
f_{2} = 245hz, m = M+1
g = 9.8m/s


Homework Equations


f=v/L, v = \sqrt{T/u}


The Attempt at a Solution


not sure where to start the problem
please help!
any help is greatly appreciated!
 
Physics news on Phys.org
Just did some plug and chuck with the equation f = v/L, substituted v = sqrt(T/u), T=mg, u = m/L, m cancels out, L = 2.45x10^-4, does this sound right?
 

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