Write the equation for a sinusoidal wave propagating in the negative \(x\) -direction with a speed of \(120 . \mathrm{m} / \mathrm{s}\), if a particle in the medium in which the wave is moving is observed to swing back and forth through a \(6.00-\mathrm{cm}\) range in \(4.00 \mathrm{~s}\). Assume that \(t=0\) is taken to be the instant when the particle is at \(y=0\) and that the particle moves in the positive \(y\) -direction immediately after \(t=0\).

Short Answer

Expert verified
Question: A sinusoidal wave is observed to travel in the negative x-direction with a wave speed of 120 m/s. The oscillating particle is observed to swing back and forth through a 6.00 cm range and take 4.00 seconds to complete an oscillation. Find the equation of the wave. Answer: The equation of the wave is given by y(x,t) = 0.030 * cos(π/240 * x + 0.5π * t - π/2), where x is the position, and t is the time.

Step by step solution

01

Find the amplitude of the wave

The amplitude (A) is the maximum displacement of the particles from their mean position. In this problem, we are given that a particle is observed to swing back and forth through a 6.00 cm range. Therefore, the amplitude of the wave is half of this range. A = 6.00 cm / 2 = 3.00 cm = 0.030 m
02

Find the frequency and angular frequency of the wave

The time taken for a complete oscillation of the particle is given as 4.00 seconds. This time is called the time period (T) of the wave. The frequency (f) is the inverse of the time period. f = 1 / T = 1 / 4.00 s = 0.25 Hz The angular frequency (ω) is related to the frequency by the following formula: ω = 2πf ω = 2π(0.25 Hz) = 0.5π rad/s
03

Determine the wave number (k) of the wave

The wave speed (v) is given as 120 m/s. The wave number (k) is related to the wave speed and angular frequency by the following formula: v = ω / k Rearrange the equation and solve for k: k = ω / v = (0.5π rad/s) / (120 m/s) = π/240 rad/m
04

Write the equation for the sinusoidal wave

Since the wave is propagating in the negative x-direction and particles move in the positive y-direction immediately after t=0, the equation for the sinusoidal wave can be represented as: y(x,t) = A * cos(kx + ωt + φ) Here, φ is the phase constant. As we are assuming that at t=0, the particle is at y=0 and moves in the positive y-direction immediately after t=0, this means the wave is at its mean position and hence has a phase constant of -π/2. φ = -π/2 Now, substitute the values of A, k, ω, and φ in the equation: y(x,t) = 0.030 * cos(π/240 * x + 0.5π * t - π/2)

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

Hiking in the mountains, you shout "hey," wait \(2.00 \mathrm{~s}\) and shout again. What is the distance between the sound waves you cause? If you hear the first echo after \(5.00 \mathrm{~s}\), what is the distance between you and the point where your voice hit a mountain?

Two waves traveling in opposite directions along a string fixed at both ends create a standing wave described by \(y(x, t)=1.00 \cdot 10^{-2} \sin (25 x) \cos (1200 t) .\) The string has a linear mass density of \(0.01 \mathrm{~kg} / \mathrm{m},\) and the tension in the string is supplied by a mass hanging from one end. If the string vibrates in its third harmonic, calculate (a) the length of the string, (b) the velocity of the waves, and (c) the mass of the hanging mass.

A traveling wave propagating on a string is described by the following equation: $$ y(x, t)=(5.00 \mathrm{~mm}) \sin \left(\left(157.08 \mathrm{~m}^{-1}\right) x-\left(314.16 \mathrm{~s}^{-1}\right) t+0.7854\right) $$ a) Determine the minimum separation, \(\Delta x_{\min }\), between two points on the string that oscillate in perfect opposition of phases (move in opposite directions at all times). b) Determine the separation, \(\Delta x_{A B}\), between two points \(A\) and \(B\) on the string, if point \(B\) oscillates with a phase difference of 0.7854 rad compared to point \(A\). c) Find the number of crests of the wave that pass through point \(A\) in a time interval \(\Delta t=10.0 \mathrm{~s}\) and the number of troughs that pass through point \(B\) in the same interval. d) At what point along its trajectory should a linear driver connected to one end of the string at \(x=0\) start its oscillation to generate this sinusoidal traveling wave on the string?

Why do circular water waves on the surface of a pond decrease in amplitude as they travel away from the source?

Suppose that the tension is doubled for a string on which a standing wave is propagated. How will the velocity of the standing wave change? a) It will double. c) It will be multiplied by \(\sqrt{2}\). b) It will quadruple. d) It will be multiplied by \(\frac{1}{2}\).

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.

Sign-up for free