A fire engine is driving directly away from a solid wall at 30 m/s on a hot 30.0

Question

A fire engine is driving directly away from a solid wall at 30 m/s on a hot 30.0 degrees celsius day while its siren emits a steady 485. Hz sound. The speed of sound on this day is 349 m/s.

a)Compute the frequency heard by a stationary listener standing near the wall.

b)Compute the wavelength of the waves as they approach the stationary listener.

c)A firefighter on the back of the fire engine hears the sound waves after they are reflected from the wall. What is the frequency of this reflected wave as heard by this firefighter?

Explanation / Answer

Here Is the method to solve A: Doppler effect for a receding source = (F intial)/(1 + vsource/velocity of sound) B: Lamda = Velocity/Frequency (solved for up in A) C: This is done in 2 parts: The first part you already did since you were the receding source. The 2nd part is now the wall is the source and you're the receding observer. So Frequency for receding source is F = (1 - V initial/ V)*Frequency of source. Pretty much just plug in your numbers and solve for your answers

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.