Exam 18: Superposition and Standing Waves

Tuning forks #1, #2, and #3 each have slightly different frequencies.When #1 and #2 are sounded together, a beat frequency of 3 Hz results. When #2 and #3 are sounded together, a beat frequency of 5 Hz results. If the frequency of #1 is 100 Hz, which of the following cannot be the frequency of #3?

A string is stretched and fixed at both ends, 200 cm apart. If the density of the string is 0.015 g/cm, and its tension is 600 N, what is the wavelength (in cm) of the first harmonic?

A length of organ pipe is closed at one end. If the speed of sound is 344 m/s, what length of pipe (in cm) is needed to obtain a fundamental frequency of 50 Hz?

Two harmonic waves are described by What is the magnitude of the displacement (in cm) of this wave at x = 3 cm and t = 5 sec?

Which of the following wavelengths could NOT be present as a harmonic on a 2 m long string?

Two harmonic waves are described by What is the amplitude of the resultant wave?

Two harmonic waves are described by What is the phase (in rad) of the resultant wave when x = t = 0?

The superposition of two waves and at the location x = 0 in space results in

Which of the following frequencies could NOT be present as a standing wave in a 2m long organ pipe open at both ends? The fundamental frequency is 85 Hz.

A speaker is producing 30 W of sound. At which of the following frequencies would it sound the loudest?

An organ pipe open at both ends has a radius of 4.0 cm and a length of 6.0 m. What is the frequency (in Hz) of the third harmonic? (Assume the velocity of sound is 344 m/s.)

Superposition of waves can occur

When two organ pipes each closed at one end sound a perfect fifth, such as two notes with fundamental frequencies at 440 Hz and 660 Hz, both pipes produce overtones. Which choice below correctly describes overtones present in both pipes?

If a plane is flying at a speed so that the apex half-angle of its shockwave is 30°, what is its speed if the speed of sound is 320 m/s?

The figure below shows the positions of particles in a longitudinal standing wave. One quarter period later the particle distribution is shown in

A string with a fixed frequency vibrator at one end is undergoing resonance with 4 antinodes when under tension T₁. When the tension is slowly increased the resonance condition disappears until tension T₂ is reached, there being no resonances occurring between these two tensions. How many antinodes are there in this new resonance?

The superposition of two waves, and , results in a wave with a wavelength of

Exhibit 18-1 The figure below shows wave crests after a stone is thrown into a pond. Use this exhibit to answer the following question(s). -Refer to Exhibit 18-1. The phase difference in radians between points A and D is

On a day when the speed of sound in the upper air is 320 m/s, you fly coast to coast in the United States, a distance of about 4 850 km, in about one hour, if the Mach number for the speed of your airplane is about

Two organ pipes, a pipe of fundamental frequency 440 Hz, closed at one end, and a pipe of fundamental frequency 660 Hz, open at both ends, produce overtones. Which choice below correctly describes overtones present in both pipes?