Exam 14: Sound

To produce an "A" note (440. Hz) at 20.° C, a saxophone must create how long an effective air column?

The wavelength in air (temperature of 20°C) of a sound wave of frequency 0.50 kHz is

Consider the standing wave on a guitar string and the sound wave generated by the guitar as a result of this vibration. What do these two waves have in common?

The decibel level of sound is related to its

Given 4 tuning forks of frequency 446, 440, 443, and 449 Hz, how many different beat frequencies could be produced and what are they?

Two adjacent sources each emit a frequency of 800. Hz in air where the velocity of sound is 340. m/s. How much farther back would the first source have to be moved so an observer in front of the sources would hear no sound?

Suppose you hear a car approaching and its horn is heard as a 3037. Hz tone. After passing, you hear 2430. Hz. (a) What was the Mach number of the car? (b) What is the speed of sound if the outside temperature is 19.°C? (c) How fast was the car moving, in meters per second?

On a day when the speed of sound in air is 340. m/s, a bat emits a shriek whose echo reaches it 25.0 ms later. How far away was the object that reflected back the sound?

For 440. Hz sound in 20.°C air, which of the following path differences would result in constructive interference?

What is the ratio of the speed of sound in air at 0° C to the speed at 100° C?

Sound vibrations with frequencies less than 20 Hz are called

James is listening to the same tone coming from two speakers, one 3.49 m away and the other 3.10 m distant. At his position the two tones destructively interfere. (a) What is the largest possible wavelength of the tone? (b) If the air temperature is 30.° C, what is the lowest possible frequency?

Consider a sound intensity of 16. × 10^-8 W/m². (a) What is the sound intensity level? (b) At twice the distance from the source, what would be the intensity level? (c) At how many times the original distance would the intensity level decrease by 12. db?

Two violin strings, vibrating at 880. Hz and 876. Hz respectively, will cause a beat frequency of

A trombone or a trumpet can be considered a(n)

An organ pipe open at both ends has a length of 0.800 m. If the velocity of sound in air is 340. m/s, what are the frequencies of the second and third harmonics?

Estimate by what percent the perceived frequency of speech changes due to a talking person walking away from another person at rest at a speed of 3 m/s.

A train moving 30. m/s approaches a station and sounds its whistle and passengers standing at the station hear a pitch of 440. cycles/second. What pitch will be heard when the train is at rest at the station? (assume the air temperature is 20.°C)

Only odd harmonics can be produced in a(n) ________ organ pipe.

How many decibels correspond to a sound intensity of 7.0 × 10^-7 W/ m²?