/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 44 One string of a certain musical ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

One string of a certain musical instrument is 75.0 \(\mathrm{cm}\) long and has a mass of 8.75 \(\mathrm{g}\) . It is being played in a room where the speed of sound is 344 \(\mathrm{m} / \mathrm{s}\) . (a) To what tension must you adjust the string so that, when vibrating in its second overtone, it produces sound of wavelength 3.35 \(\mathrm{cm} ?\) (b) What frequency sound does this string produce in its fundamental mode of vibration?

Short Answer

Expert verified
(a) Adjust the tension to about 21.36 N. (b) The fundamental frequency is approximately 229 Hz.

Step by step solution

01

Convert Units

First, convert the mass of the string from grams to kilograms since other units are in the SI system. The mass is 8.75 g, which is equal to 8.75 × 10^{-3} kg. Also, convert the wavelength from cm to meters: 3.35 cm = 3.35 × 10^{-2} m.
02

Apply Formula for Wave Speed on String

The wave speed on a string, \(v\), is determined by the formula \(v = \sqrt{\frac{T}{\mu}}\), where \(T\) is the tension and \(\mu\) is the mass per unit length of the string. Calculate \(\mu\) as \(\mu = \frac{m}{L} = \frac{8.75 \times 10^{-3} \, \text{kg}}{0.75 \, \text{m}}\).
03

Find Speed of String for Second Overtone

The frequency \(f\) of the second overtone is related to the wavelength \(\lambda\) by \(f = \frac{v}{\lambda}\). The second overtone corresponds to the third harmonic, thus \(\lambda_3 = \frac{2L}{3}\). Given \(\lambda = 3.35 \times 10^{-2} \, \text{m}\), calculate the wave speed \(v\) using \(f = \frac{344}{\lambda}\).
04

Calculate Tension Required

Using the expression for wave speed from Step 2, set \(v = \sqrt{\frac{T}{\mu}}\) equal to the value found in Step 3. Solve for the tension \(T\): \(T = \mu v^2\).
05

Find Frequency for Fundamental Mode

For the fundamental mode, the wavelength is \(\lambda_1 = 2L\). Calculate the frequency using \(f_1 = \frac{v}{\lambda_1} = \frac{v}{2L}\), where \(v\) is the wave speed found from Step 3.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Overtones in Music
When we talk about overtones in music, we're referring to the higher frequency sounds that follow the fundamental frequency played by a musical instrument. Overtones are a key aspect of music theory, influencing how we perceive different sounds and musical notes.

In the context of stringed instruments, overtones correspond to the harmonics that are produced when the string vibrates in segments, rather than its entire length. The second overtone, for instance, is actually the third harmonic. This means that the string vibrates in three equal sections, producing a pitch higher than the fundamental frequency.

Understanding overtones helps musicians and physicists alike make sense of how different pitches are produced. It's also crucial when tuning instruments, as these overtones need to align properly with the fundamental tones to create the desired harmony.

Overtones play a vital role in the richness and complexity of music, contributing to the timbre, or the "color," of the sound produced by an instrument.
Frequency Calculation
Calculating frequency requires understanding the relationship between frequency (\(f\), wavelength (\(\lambda\), and wave speed (\(v\). The fundamental formula connecting these is \(f = \frac{v}{\lambda}\). In musical instruments, this formula lets us determine the frequency of sounds that strings or air columns produce.

For instance, considering the fundamental mode, the wavelength (\(\lambda_1\) is twice the length of the string. When calculating the frequency of the fundamental note, you can use the formula \(f_1 = \frac{v}{2L}\), where \(L\) is the length of the string.

Each overtone, such as the second overtone, uses a different segment of the string's wavelength. For example, the second overtone ties closely to its frequency calculation given that it's the third harmonic. It illustrates how changes in string segmentation affect pitch.

Understanding these calculations is critical in the fields of acoustics and music, providing insight into how various sounds are produced and how harmonic relationships are formed.
Wave Speed on a String
Wave speed on a string is pivotal for tuning and modifying the sound properties of stringed instruments. The wave speed (\(v\) can be calculated using the tension (\(T\) in the string and the mass per length (\(\mu\) of the string. The formula for wave speed is \(v = \sqrt{\frac{T}{\mu}}\).

\(\mu\), the linear mass density, is found by dividing the string's mass by its length, \(\mu = \frac{m}{L}\).
  • Higher tension results in faster wave speed, producing higher pitches.
  • Thicker strings have higher values of \(\mu\), resulting in slower wave speeds.
Understanding the interaction of tension and mass per unit length is fundamental to manipulating sound characteristics.

When players adjust the tension of strings, they are effectively modifying the wave speed, which impacts the frequency (and therefore the pitch) of the sound produced. This concept is not only essential for musicians but also for understanding wave mechanics in physical systems.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Guitar String. One of the 63.5 -cm-long strings of an ordinary guitar is tuned to produce the note \(\mathbf{B}_{3}\) (frequency 245 \(\mathrm{Hz} )\) when vibrating in its fundamental mode. (a) Find the speed of transverse waves on this string. (b) If the tension in this string is increased by \(1.0 \%,\) what will be the new fundamental frequency of the string? (c) If the speed of sound in the surrounding air is 344 \(\mathrm{m} / \mathrm{s}\) , find the frequency and wavelength of the sound wave produced in the air by the vibration of the \(\mathrm{B}_{3}\) string. How do these compare to the frequency and wavelength of the standing wave on the string?

Tsunami! On December \(26,2004,\) a great earthquake occurred off the coast of Sumatra and triggered immense waves (tsunami) that killed some \(200,000\) people. Satellites observing these waves from space measured 800 \(\mathrm{kn}\) from one wave crest to the next and a period between waves of 1.0 hour. What was the speed of these waves in \(\mathrm{m} / \mathrm{s}\) and \(\mathrm{km} / \mathrm{h}\) ? Does your answer help you understand why the waves caused such devastation?

A transverse sine wave with an amplitude of 2.50 \(\mathrm{mm}\) and a wavelength of 1.80 \(\mathrm{m}\) travels from left to right along a long, horizontal, stretched string with a speed of 36.0 \(\mathrm{m} / \mathrm{s}\) . Take the origin at the left end of the undisturbed string. At time \(t=0\) the left end of the string has its maximum upward displacement, (a) What are the frequency, angular frequency, and wave number of the wave? (b) What is the function \(y(x, t)\) that describes the wave? (c) What is \(y(t)\) for a particle at the left end of the string? (d) What is \(y(t)\)for a particle 1.35 \(\mathrm{m}\) to the right of the origin? (e) What is the maximum magnitude of transverse velocity of any particle of the string? (f) Find the transverse displacement and the transverse velocity of a particle 1.35 \(\mathrm{m}\) to the right of the origin at time \(t=0.0625 \mathrm{s}\) .

A wire with mass 40.0 \(\mathrm{g}\) is stretched so that its ends are tied down at points 80.0 \(\mathrm{cm}\) apart. The wire vibrates in its fundamental mode with frequency 60.0 \(\mathrm{Hz}\) and with an amplitude at the antinodes of 0.300 \(\mathrm{cm}\) . (a) What is the speed of propagation of transverse waves in the wire? (b) Compute the tension in the wire. (c) Find the maximum transverse velocity and acceleration of particles in the wire.

A piano wire with mass 3.00 \(\mathrm{g}\) and length 80.0 \(\mathrm{cm}\) is stretched with a tension of 25.0 \(\mathrm{N}\) . A wave with frequency 120.0 \(\mathrm{Hz}\) and amplitude 1.6 \(\mathrm{mm}\) travels along the wire. (a) Calculate the average power carried by the wave. (b) What happens to the average power if the wave amplitude is halved?

See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.