Solving Harmonics Problems: Wavelength & Frequency

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The discussion revolves around a physics problem involving a string tied to a wall and a weight over a pulley, focusing on the effects of changing weight and string length on wavelength and frequency in the first harmonic. Doubling the weight will increase the tension in the string, which in turn affects the frequency, while the wavelength remains constant in terms of its relationship to the frequency. When the length of the vibrating part of the string is halved without changing the weight, the wavelength will also decrease, reflecting the relationship between string length and harmonic frequency. Participants express confusion about how to derive new values for wavelength and frequency based on the changes described. Understanding the fundamental relationships between tension, mass per unit length, and harmonic properties is essential for solving these problems.
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Homework Statement



One end of a horizontal string is tied to a wall, and the other end is tied to an object with weight W that hangs over a pulley to hold the string taut. The object is large enough that the string never moves at the pulley. Under these conditions, the string vibrates with wavelength lambda and frequency f in its first harmonic.

If we add enough weight to double W without appreciably stretching the string, what will be the wavelength (in terms of lambda and f) of the string's first harmonic vibration?

If we add enough weight to double W without appreciably stretching the string, what will be the frequency (in terms of lambda and f) of the string's first harmonic vibration?

If we do not change W, but move the pulley so that the vibrating part of the string is half as long, what will be the wavelength (in terms of\lambda and f) of the string in its first harmonic?

Homework Equations


v=lambdaf v=sqrt(F/(m/L)) lambda=(2L)/n


The Attempt at a Solution



Having a hard time deciphering what the question is asking, or how to get there.
 
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The question is asking you to find new values in terms of the old wavelength and frequency.

For the first and second part, what would adding weight increase?

For the third part, what does first harmonic mean in terms of wavelength?
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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