/*! 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} Q21PE People with good hearing can per... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 17: Q21PE (page 629)

People with good hearing can perceive sounds as low in level as\( - 8.00\;{\rm{dB}}\)at a frequency of\(3000\;{\rm{Hz}}\). What is the intensity of this sound in watts per meter squared?

Short Answer

Expert verified

The intensity is \(1.58 \times {10^{ - 13}}\;{\rm{W/}}{{\rm{m}}^{\rm{2}}}\).

Step by step solution

01

Given data

The intensity level is \(d = - 8.00\;{\rm{dB}}\).

The frequency is \(f = 3000\;{\rm{Hz}}\).

02

Definition of sound intensity

At low frequencies, loudness requires more intensity to perceive equal loudness, whereas the mid-frequency range requires less intensity to perceive the same.

03

Calculation of the intensity of the first sound

The intensity of the sound is,

\(d = 10\log \frac{I}{{{{10}^{ - 12}}}}\)

So,

\(\begin{align}- 8.00 &= 10\log \frac{I}{{{{10}^{ - 12}}}}\\ - 0.8 &= \log \frac{I}{{{{10}^{ - 12}}}}\\{10^{ - 0.8}} &= \frac{I}{{{{10}^{ - 12}}}}\\I &= 1.58 \times {10^{ - 13}}\;{\rm{W/}}{{\rm{m}}^{\rm{2}}}\end{align}\)

The intensity of this sound in watts per meter squared is \(1.58 \times {10^{ - 13}}\;{\rm{W/}}{{\rm{m}}^{\rm{2}}}\).

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 91影视!

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) Students in a physics lab are asked to find the length of an air column in a tube closed at one end that has a fundamental frequency of 256 Hz. They hold the tube vertically and fill it with water to the top, then lower the water while a 256 Hz tuning fork is rung and listen for the first resonance. What is the air temperature if the resonance occurs for a length of 0.336 m?

(b) At what length will they observe the second resonance (first overtone)?

A spectator at a parade receives an\(888\;{\rm{Hz}}\)tone from an oncoming trumpeter who is playing an\(880\;{\rm{Hz}}\)note. At what speed is the musician approaching if the speed of sound is\({\rm{338}}\;{\rm{m/s}}\)?

(a) Ear trumpets were never very common, but they did aid people with hearing losses by gathering sound over a large area and concentrating it on the smaller area of the eardrum. What decibel increase does an ear trumpet produce if its sound gathering area is\(900\;{\rm{c}}{{\rm{m}}^{\rm{2}}}\)and the area of the eardrum is\(0.500\;{\rm{c}}{{\rm{m}}^{\rm{2}}}\), but the trumpet only has an efficiency of\(5.00\% \)in transmitting the sound to the eardrum? (b) Comment on the usefulness of the decibel increase found in part (a)

A community is concerned about a plan to bring train service to their downtown from the town鈥檚 outskirts. The current sound intensity level, even though the rail yard is blocks away, is 70 dB downtown. The mayor assures the public that there will be a difference of only 30 dB in sound in the downtown area. Should the townspeople be concerned? Why?

Question: (a) What is the decibel level of a sound that is twice as intense as a \(90.0\;{\rm{dB}}\)sound? (b) What is the decibel level of a sound that is one-fifth as intense as a \(90.0\;{\rm{dB}}\)?
See all solutions

Recommended explanations on Physics Textbooks

Electric Charge Field and Potential

Read Explanation

Torque and Rotational Motion

Read Explanation

Conservation of Energy and Momentum

Read Explanation

Dynamics

Read Explanation

Measurements

Read Explanation

Further Mechanics and Thermal Physics

Read Explanation
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.