A stationary source produces a sound wave at a frequency of 100 Hz. The wave travels at 1125 feet per second. A car is moving toward

Question

the sound source at a speed of 100 feet per second.
What is the wavelength of the stationary sound source and the wavelength that a person in the car perceives?
(1 point)
wavelength of the stationary source: 12.25 ft; perceived wavelength: 11.25 ft
wavelength of the stationary source: 11.25 ft; perceived wavelength: 12.25 ft
wavelength of the stationary source: 11.25 ft; perceived wavelength: 10.25 ft
wavelength of the stationary source: 10.25 ft; perceived wavelength: 11.25 ft

Answer 1

To find the wavelength of the stationary source, we use the formula:

wavelength = speed of sound / frequency

wavelength = 1125 ft/s / 100 Hz
wavelength = 11.25 ft

Next, we need to find the perceived wavelength by the person in the car. This can be found using the formula:

perceived wavelength = (speed of sound + speed of car) / frequency

perceived wavelength = (1125 ft/s + 100 ft/s) / 100 Hz
perceived wavelength = 1225 ft/s / 100 Hz
perceived wavelength = 12.25 ft

Therefore, the correct answer is:
wavelength of the stationary source: 11.25 ft; perceived wavelength: 12.25 ft.