5.
The pitch of the siren of a moving fire truck changes from high to low as the fire truck passes by. What property of a sound wave changes as the fire truck goes by? (1 point)
A.amplitude
B.density
C.temperature
D. frequency***
I think your answer is right; the frequency changes as the fire truck goes by. However, I have a problem with the statement that the pitch changes from high to low as the fire truck passes by. As the fire truck comes toward you the frequency increases; after the fire truck passes the frequency decreases. So I would state that the pitch increases as the fire truck is coming and the pitch decreases after the fire truch passes.
It is a homework question so i can not change it! Thanks!!
I understand that but I wanted to clear the air.
so the answer is?? im so lost, i have connexus and im doing 7th grade "Lesson 9: Waves and Electromagnetic Radiation Unit Test" and rlly need help, so if anyone can yk slide the answers or help i'd love that. anyways bye
The correct answer is D. frequency.
To understand why this is the case, we need to understand a few concepts about sound waves. Sound waves are vibrations that travel through a medium, such as air, and they consist of compressions and rarefactions. The frequency of a sound wave is the number of complete cycles of compression and rarefaction that occur in one second. It is measured in Hertz (Hz).
When a fire truck approaches you, the sound waves it produces are compressed or squeezed closer together due to the Doppler effect. This increase in frequency results in a higher pitch because there are more compressions and rarefactions passing by your ear per second.
Once the fire truck passes you, the sound waves are stretched out or expanded, resulting in a decrease in frequency, and thus a lower pitch. This change in frequency is what causes the siren to go from a high pitch to a low pitch as the fire truck moves past you.
To summarize, as the fire truck passes by, the frequency of the sound waves changes, resulting in a change in pitch from high to low. Therefore, the correct answer is D. frequency.