Homework Help is Here – Start Your Trial Now!
Science
Advanced Physics
5. At a rock concert, a dB meter registered 130 dB when placed 2.5 m in front of a loudspeaker on the stage. (A) What was the power output of the speaker? (B) How far away would the intensity level be a somewhat reasonable 90 dB?

5. At a rock concert, a dB meter registered 130 dB when placed 2.5 m in front of a loudspeaker on the stage. (A) What was the power output of the speaker? (B) How far away would the intensity level be a somewhat reasonable 90 dB?

icon
Related questions
Question
100%
Could you help me with number 5 please
W d) Calculate the next two frequencies by tripling and quintupling. f3= Hz fs = Hz Which sounds lower when the fundamental is sounded? Open/Closed 5. At a rock concert, a dB meter registered 130 dB when placed 2.5 m in front of a loudspeaker on the stage. (A) What was the power output of the speaker? (B) How far away would the intensity level be a somewhat reasonable 90 dB? A) i) Write the equation that relates intensity level, ß (decibels) to intensity, I (W/m²) and the threshold of hearing, Io = 10-¹2 W/m². В (equation to define sound intensity level, Eq. 16-16) ii) Plug in numbers, (dB) = 10 log I/ iii) Solve for I. I = W/m² iv) Assume a uniform spherical spreading of the sound. Write an equation for the surface area of a sphere with radius r. Area v) Intensity is defined as power per area. Write an equation relating intensity, power, and radius using your answer to (iv). I = P/ vi) Use I from (c) and r = 2.5 m to determine the power, P. P = IA = W B) i) To answer the (B) part of the problem, convert the new sound intensity level (B' = 90 dB) into intensity. I'= (W/m²) P ii) Using the power, P, of the source, determine the new radius from I'= 477-¹2 r' = m (check for reasonableness, to reduce decibel level, you should move farther away than original distance) G
Transcribed Image Text:W d) Calculate the next two frequencies by tripling and quintupling. f3= Hz fs = Hz Which sounds lower when the fundamental is sounded? Open/Closed 5. At a rock concert, a dB meter registered 130 dB when placed 2.5 m in front of a loudspeaker on the stage. (A) What was the power output of the speaker? (B) How far away would the intensity level be a somewhat reasonable 90 dB? A) i) Write the equation that relates intensity level, ß (decibels) to intensity, I (W/m²) and the threshold of hearing, Io = 10-¹2 W/m². В (equation to define sound intensity level, Eq. 16-16) ii) Plug in numbers, (dB) = 10 log I/ iii) Solve for I. I = W/m² iv) Assume a uniform spherical spreading of the sound. Write an equation for the surface area of a sphere with radius r. Area v) Intensity is defined as power per area. Write an equation relating intensity, power, and radius using your answer to (iv). I = P/ vi) Use I from (c) and r = 2.5 m to determine the power, P. P = IA = W B) i) To answer the (B) part of the problem, convert the new sound intensity level (B' = 90 dB) into intensity. I'= (W/m²) P ii) Using the power, P, of the source, determine the new radius from I'= 477-¹2 r' = m (check for reasonableness, to reduce decibel level, you should move farther away than original distance) G
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer