Physics with Application; Acoustics; Trumpet

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Homework Help Overview

The discussion revolves around a problem in acoustics, specifically focusing on the intensity of sound as it relates to a hearing trumpet's shape and dimensions. The problem involves calculating the factor by which the trumpet increases sound intensity and the corresponding change in decibels.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the need to calculate the areas of the trumpet's wide and narrow ends to apply the intensity formulas. There is an attempt to relate intensity changes to power and area, with some participants expressing confusion over the mathematical expressions presented.

Discussion Status

The discussion is ongoing, with participants providing suggestions and seeking clarification on the calculations involved. Some guidance has been offered regarding the need to find the areas for the calculations, but there is no explicit consensus on the approach yet.

Contextual Notes

Participants are navigating the problem with varying levels of understanding, and there is an emphasis on the importance of showing attempts at solving the problem as per forum guidelines.

MAtkinson
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From Acoustics, Resonance, Energy, Power, Intensity and The Doppler Effect

Homework Statement



An old-fashioned hearing trumpet has the shape of a flared funnel, with a diameter of 8 cm at its wide end and a diameter of 0.7 cm at its narrow end. Suppose that all of the sound energy that reaches the wide end is funneled into the narrow end. By what factor does this hearing trumpet increase the intensity of sound (measured in W/m2)? By how many decibels does it increase the intensity level of sound?


Homework Equations



Intensity = Power / Area

Intensity = Energy / (Time)*(Area)

Intensity Level = 10*Log(Intensity/10^(-12)) (db)

The Attempt at a Solution



...
 
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Welcome to PF!
We have a policy of ignoring questions where there is no attempt made on the problem. But I can make an exception since it is your first post, and offer a suggestion to get you started.

Start by finding the areas, at the input end and at the output to ear end. Put them into your formulas.
 
... Thanks for the insightful reply. I understand it's not the most difficult question, nonetheless I am getting stuck.

10^((deltaIntensityLevel)/10-12)=Power/DeltaCircleArea
 
I don't understand that at all.
Were you able to find the two areas?
Maybe use intensity = power/area twice, once for each end.
 

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