Assignment B

Lab: Sound Waves Post-Lab Knowledge Check PHYS 242

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Sound Waves Suppose that you are listening to a musician who is playing the cello (also known as a cellist). They begin by playing a sound at a given frequency. They then switch to a note with a lower pitch. The sound is similar to the beginning of the Jaws theme, as demonstrated by this child on YouTube: https://www.youtube.com/watch?v=uR689WR4fZM

A. When the cellist changes between these two notes, what happens to: a. the frequency of the sound wave?

b. the wavelength of the sound wave?

c. the speed of the sound wave?

For each question, explain how you know.

B. Suppose the musician decreases the amplitude of the sound wave. What happens to the resulting sound that you hear?

C. Imagine that you are standing in front of the cellist.1 Plot the pressure changes at your position as a function of time.

1 Of course you are at least 6 feet away from the cellist to maintain social distancing.