A guitar string vibrates at a frequency of 330 Hz with a wavelength 1.40 m. The frequency and wavelength of this sound in air (20°C) as it reaches our ears is

(a) same frequency, same wavelength.

(b) higher frequency, same wavelength.

(c) lower frequency, same wavelength.

(d) same frequency, longer wavelength.

(e) same frequency, shorter wavelength.

Short Answer

Expert verified

The correct option is (e).

Step by step solution

01

Frequency and Wavelength

Wavelengthcan be defined as the distance between two successive crests or troughs of a wave.It is measured in lengths such as meters, centimeters, millimeters, nanometers, and others.

Frequency is the speed of vibration, and this determines the pitch of the sound. It is measured in Hertz.

02

Explanation

As the string oscillates, it causes the air to vibrate at the same frequency. Therefore, the sound wave will have the same frequency as the guitar string, so answers (b) and (c) are incorrect. The speed of sound in the air at \({20^ \circ }\;{\rm{C}}\) temperature is \(343\;{{\rm{m}} \mathord{\left/

{\vphantom {{\rm{m}} {\rm{s}}}} \right.

\\{\rm{s}}}\). Sound speed in the string is the product of the wavelength and frequency \(462\;{{\rm{m}} \mathord{\left/

{\vphantom {{\rm{m}} {\rm{s}}}} \right.

\\{\rm{s}}}\), so the sound waves in the air have a shorter wavelength than the waves on the string.

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

Question: (III) When a player’s finger presses a guitar string down onto a fret, the length of the vibrating portion of the string is shortened, thereby increasing the string’s fundamental frequency (see Fig. 12–36). The string’s tension and mass per unit length remain unchanged. If the unfingered length of the string is l= 75.0 cm, determine the positions x of the first six frets, if each fret raises the pitch of the fundamental by one musical note compared to the neighboring fret. On the equally tempered chromatic scale, the ratio of frequencies of neighboring notes is 21/12.

Figure 12-36

Question: Two loudspeakers are at opposite ends of a railroad car as it moves past a stationary observer at\({\bf{12}}{\bf{.0}}\,{\bf{m/s}}\), as shown in Fig. 12–41. If the speakers have identical sound frequencies of \({\bf{348}}\,{\bf{Hz}}\), what is the beat frequency heard by the observer when (a) he listens from position A, in front of the car, (b) he is between the speakers, at B, and (c) he hears the speakers after they have passed him, at C?

Fig. 12-41

The sound level 8.25 m from a loudspeaker, placed in the open, is 115 dB. What is the acoustic power output (W) of the speaker, assuming it radiates equally in all directions?

A space probe enters the thin atmosphere of a planet where the speed of sound is only about 42 m/s. (a) What is the probe’s Mach number if its initial speed is 15,000 km/h? (b) What is the angle of the shock wave relative to the direction of motion?

If two firecrackers produce a combined sound level of 85 dB when fired simultaneously at a certain place, what will be the sound level if only one is exploded? [Hint: Add intensities, not dBs.]

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