When two sound waves travel in the same direction in a medium, the displacement of a particle located at \(\mathrm{x}\) at time \(\mathrm{t}\) is given by \(\mathrm{y}_{1}=0.05 \cos (0.50 \mathrm{px}-100 \mathrm{pt}) \&\) \(\mathrm{y}_{2}=0.05 \cos (0.46 \mathrm{px}-92 \mathrm{pt})\), where \(\mathrm{y}_{1}, \mathrm{y}_{2}\) and \(\mathrm{x}\) are in meter and \(t\) is in seconds. What is the speed of sound in the medium ? (A) \(332 \mathrm{~m} / \mathrm{s}\) (B) \(100 \mathrm{~m} / \mathrm{s}\) (C) \(92 \mathrm{~m} / \mathrm{s}\) (D) \(200 \mathrm{~m} / \mathrm{s}\)

Short Answer

Expert verified
The speed of sound in the medium is \(92 \:\text{m/s}\) (option C).

Step by step solution

01

Write down the given equations

We are given the equations: \(y_1 = 0.05 \cos(0.50x - 100t)\) \(y_2 = 0.05 \cos(0.46x - 92t)\)
02

Identify the phase velocity terms

The term inside the cosine brackets represents the phase of the wave. So, we identify the phase velocities for both waves: For \(y_1\), the phase is \(0.50x - 100t\) For \(y_2\), the phase is \(0.46x - 92t\)
03

Extract the coefficients of x and t and find the ratio

From the phases of both waves, extract the coefficients of x and t: \(Y_1 = 0.05 \cos(0.50x - 100t)\) has coefficients 0.50 for x and -100 for t. \(Y_2 = 0.05 \cos(0.46x - 92t)\) has coefficients 0.46 for x and -92 for t. Now, we find the ratio of coefficients for both waves: \(\frac{0.50}{-100} = \frac{0.46}{-92}\)
04

Solve for the speed of sound

Now, we solve the equation found in step 3, to get the speed of sound, v: \(\frac{0.50}{-100} = \frac{0.46}{-92}\) Cross-multiplying, we get: \(-100 \times 0.46 = -92 \times 0.50\) Divide both sides by -1 and simplify: \(100 \times 0.46 = 92 \times 0.50\) Divide both sides by 0.5: \(100 \times 0.92 = 92\) Since both waves are traveling in the same medium, their average speed is the speed of sound in the medium: \(v = 0.92 \times 100 = 92 \:\text{m/s}\) Therefore, the speed of sound in the medium is 92 m/s (option C).

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 Vaia!

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

A wave \(\mathrm{y}=\mathrm{a} \sin (\omega \mathrm{t}-\mathrm{kx})\) on a string meets with another wave producing a node at \(\mathrm{x}=0 .\) Then the equation of the unknown wave is \(\ldots \ldots \ldots\) (A) \(y=a \sin (\omega t+k x)\) (B) \(\mathrm{y}=-\mathrm{a} \sin (\omega \mathrm{t}+\mathrm{kx})\) (C) \(\mathrm{y}=\mathrm{a} \sin (\omega \mathrm{t}-\mathrm{kx})\) (D) \(\mathrm{y}=-\mathrm{a} \sin (\omega \mathrm{t}-\mathrm{kx})\)

For the following questions, statement as well as the reason(s) are given. Each questions has four options. Select the correct option. (a) Statement \(-1\) is true, statement \(-2\) is true; statement \(-2\) is the correct explanation of statement \(-1\). (b) Statement \(-1\) is true, statement \(-2\) is true but statement \(-2\) is not the correct explanation of statement \(-1\). (c) Statement \(-1\) is true, statement \(-2\) is false (d) Statement \(-1\) is false, statement \(-2\) is true (A) a (B) \(\mathrm{b}\) (C) \(c\) (D) \(\mathrm{d}\) Statement \(-1:\) For a particle executing SHM, the amplitude and phase is decided by its initial position and initial velocity. Statement \(-2:\) In a SHM, the amplitude and phase is dependent on the restoring force. (A) a (B) \(b\) (C) \(\mathrm{c}\) (D) \(\mathrm{d}\)

A spring is attached to the center of a frictionless horizontal turn table and at the other end a body of mass \(2 \mathrm{~kg}\) is attached. The length of the spring is \(35 \mathrm{~cm}\). Now when the turn table is rotated with an angular speed of \(10 \mathrm{rad} \mathrm{s}^{-1}\), the length of the spring becomes \(40 \mathrm{~cm}\) then the force constant of the spring is $\ldots \ldots \mathrm{N} / \mathrm{m}$. (A) \(1.2 \times 10^{3}\) (B) \(1.6 \times 10^{3}\) (C) \(2.2 \times 10^{3}\) (D) \(2.6 \times 10^{3}\)

A rocket is moving at a speed of \(130 \mathrm{~m} / \mathrm{s}\) towards a stationary target. While moving, it emits a wave of frequency $800 \mathrm{~Hz}$. Calculate the frequency of the sound as detected by the target. (Speed of wave \(=330 \mathrm{~m} / \mathrm{s}\) ) (A) \(1320 \mathrm{~Hz}\) (B) \(2540 \mathrm{~Hz}\) (C) \(1270 \mathrm{~Hz}\) (D) \(660 \mathrm{~Hz}\)

Length of a steel wire is \(11 \mathrm{~m}\) and its mass is \(2.2 \mathrm{~kg}\). What should be the tension in the wire so that the speed of a transverse wave in it is equal to the speed of sound in dry air at \(20^{\circ} \mathrm{C}\) temperature? (A) \(2.31 \times 10^{4} \mathrm{~N}\) (B) \(2.25 \times 10^{4} \mathrm{~N}\) (C) \(2.06 \times 10^{4} \mathrm{~N}\) (D) \(2.56 \times 10^{4} \mathrm{~N}\)

See all solutions

Recommended explanations on English 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.

Sign-up for free