Sound Intensity - Online Tutor, Practice Problems & Exam Prep

A technician is seated at 2.0 m from a speaker. A member of the congregation sits 10.0 m from the speaker. Calculate the difference in sound intensity levels as heard by the technician and congregant.

The threshold of hearing is defined using a reference frequency of 1000 Hz for a pure sine wave. The sound pressure amplitude at the threshold of hearing is defined by a pressure of 2.0 × 10^-5 Pa. Determine the intensity at the threshhold of hearing.

Building structures such as walls and ventilators play an important role in separating the inside from the outside. Interior sounds are blocked from moving out and vice versa using absorption and reflection. If a theater reduces its interior sound intensity by 75%, determine the change in sound intensity level (in dB).

A gathering hall is designed to filter noise from traveling outside by absorbing it. Suppose the walls of the hall decrease the sound intensity level by 25 dB. Determine the fraction by which the walls lower the sound intensity in W/m².

An alarm emits sound waves at a frequency of 520 Hz. The air has a temperature of 17.8° C. The wave has an amplitude of 6.00 × 10^-3 mm. What is the pressure amplitude of this wave (in Pa)?

A television set is located on a table 10.0 m away from you. It is playing music. You hear the music at an average of 15.0 dB. At what position measured from the TV set will you hear the music at a sound level of 30 dB?

Why would it be possible to determine the multiplication factor for the sound intensity that increases the sound intensity level by 22.0 dB without knowing the initial sound intensity? What is the numerical value of the factor?

Sound is recorded by a microphone using the vibrations caused by the sound on a diaphragm. If a microphone has a diaphragm diameter of 12.7 mm, how much energy does a singer singing at 90 dB supply to the diaphragm?

You're attending a concert and you're curious about the power of the loudspeakers being used. The main loudspeaker, installed on a tower on the stage, is designed to project 82% of its acoustic energy toward the audience, and 18% toward the backstage area. While standing 2.3 meters in front of and 1.2 meters below the loudspeaker, you measure a sound intensity level of 92 dB. Calculate the power output of the loudspeaker.

From the graph given below, Find the lowest and highest frequency audible to a human ear with a sound level of 60 dB.

Estimate how much a loudspeaker cone moves for an extremely loud (120 dB) sound at 50 Hz, assuming that the maximum displacement of air molecules in the sound wave is about the same as that of the speaker cone producing it. Hint: The reference sound intensity, typically in air, is $1 \times 10^{-12} \mathrm{~W} / \mathrm{m}^{2}$

A music composer owns two speakers. One has a maximum power output of 120 W, while the other has a power output of 60 W. Calculate the output wattage required for a speaker to be twice as loud as the 60 W speaker.

A large range of sound levels are audible to our ears. Calculate the ratio of the highest to lowest intensity of sound that we can hear at 500 Hz and 1000 Hz from the figure given below.

An online tune generator creates sine sound waves in the air with a displacement amplitude of 0.04 mm at f₁ = 200 Hz and f₂ = 20 kHz. What is the pressure amplitude (p_max) at each frequency?  Specify, under these conditions, if these sound frequencies are harmful to human hearing. The pressure variation that corresponds to the harm threshold is 30 Pa. 

An experiment is conducted by students to calculate the sound intensity level of a sound device in decibels (dB). Determine the sound intensity level if the students record a sound wave with an intensity of 4.5 × 10^-6 W/m².

A basketball fan is watching a basketball game on his TV. The TV speaker generates sound waves of 1.2 kHz. The displacement amplitude of the air molecules' vibrations caused by the sound waves is equal to 1.0 × 10^-8 m and the pressure amplitude is equal to 3.1 × 10^-2 Pa. Find the wavelength (λ) of the waves.

High-frequency sounds are common causes of ear damage, especially for children. The maximum sound pressure the child's ear can tolerate is about 20 Pa. A toy speaker produces pure sine sound waves with a maximum displacement of 0.002 mm. If the bulk modulus of air is B = 1.42 × 10⁵ Pa, i) find the maximum tolerable sound frequency of the produced sound wave to prevent hearing loss. ii) Will children hear at that frequency?