Physics with Application; Acoustics; Trumpet

AI Thread Summary
The discussion focuses on calculating the intensity increase of sound through an old-fashioned hearing trumpet, which has a wide end diameter of 8 cm and a narrow end of 0.7 cm. Participants emphasize the importance of determining the areas at both ends to apply the formulas for intensity and intensity level. The equations provided include Intensity = Power/Area and Intensity Level = 10*Log(Intensity/10^(-12)) in decibels. There is a suggestion to use the intensity formula for both ends to find the necessary values. The conversation highlights the need for a methodical approach to solving the problem.
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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