When the C3 key on a piano keyboard is pressed, a string inside the piano
is struck by a hammer and begins vibrating back and forth at
approximately 130 cycles per second. a. What is the frequency in Hertz of
the sound wave?
__b. Assuming the sound
wave moves with a velocity of 345 m/s, what is the wavelength of the
wave?

Part a)

Frequency of sound is 130 Hz

Part b)

Wavelength of the sound is 2.65 m

Explanation:

Part a)

Frequency of source of the sound is same as the frequency of the sound

Here we know that motion of hammer is back and fourth with frequency

f = 130 cycles per second

so frequency of sound is same as frequency of hammer motion

so we have

Part b)

As we know that the speed of sound is

v = 345 m/s

We know that the frequency of sound is

f = 130 Hz

now the wavelength is given as

the second one and the forth one are in the purple because they are opinions and the rest are in the yellow

explanation: