Question

a sound wave with a wavelength of 0.82 m passes through air, and then it passes through a glass window, where its wavelength changes to 13 m. if the sound wave has a constant frequency of 440 hz, what is its approximate speed as it passes through the glass? (the equation for wave speed is v = f × λ.)
a. 5,700 m/s
b. 350 m/s
c. 570 m/s
d. 3,500 m/s

Explanation:

Step1: Identify the formula

The formula for wave - speed is $v = f\times\lambda$, where $v$ is the wave speed, $f$ is the frequency, and $\lambda$ is the wavelength.

Step2: Substitute the values

We are given that the frequency $f = 440$ Hz and the wavelength in glass $\lambda=13$ m.
Substitute these values into the formula: $v=f\times\lambda=440\times13$.

Step3: Calculate the wave - speed

$440\times13 = 5720$ m/s, which is approximately $5700$ m/s.

Answer:

A. 5,700 m/s