Finding the amplitude of a pressure wave

Click For Summary
SUMMARY

The discussion focuses on calculating the amplitude of a pressure wave from a sound level expressed in decibels. The formula used is β = 20 log(P/P0), where P0 is the reference pressure difference of 2 x 10^-5 Pa. Given a sound level of 106 dB from a loud rock concert, participants clarify that the goal is to determine the pressure amplitude P. The correct approach involves substituting the known values into the equation to solve for P.

PREREQUISITES
  • Understanding of sound level calculations in decibels
  • Familiarity with logarithmic functions
  • Knowledge of pressure waves and their properties
  • Ability to manipulate algebraic equations
NEXT STEPS
  • Study the derivation of the decibel scale in acoustics
  • Learn how to apply logarithmic equations in physics problems
  • Explore the relationship between intensity and amplitude of sound waves
  • Practice solving problems involving sound pressure levels and amplitudes
USEFUL FOR

Students in physics or engineering, particularly those studying acoustics, sound wave properties, and related mathematical applications.

Patdon10
Messages
85
Reaction score
0

Homework Statement


The sound level in decibels is typically expressed as β = 10 log(I/I0), but since sound is a pressure wave, the sound level can be expressed in terms of a pressure difference. Intensity depends on the amplitude squared, so the expression is β = 20 log(P/P0), where P0 is the smallest pressure difference noticeable by the ear: P0 = 2. 10-5 Pa. A loud rock concert has a sound level of 106 dB, find the amplitude of the pressure wave generated by this concert.


Homework Equations





The Attempt at a Solution


I'm not really sure what this question is asking. It seems to be it's asking for the pressure amplitude? Is that correct?
If that's the case, I plugged all the numbers in and solver for p_0, but that's not right. So I guess the question I should be asking is how do I find the amplitude of a pressure wave?

I learn through examples, and I'm absolutely willing to try. This problem is from my last homework assignment (meaning it won't help my grade), I'd just like to learn how to do it. Can someone give me a nudge in the right direction?
 
Physics news on Phys.org
I'm not really sure what this question is asking. It seems to be it's asking for the pressure amplitude? Is that correct?

Yup.

f that's the case, I plugged all the numbers in and solver for p_0, but that's not right.

The question gives you p_0: it's 2*10^-5 Pa. That's the smallest pressure amplitude the ear is sensitive to. You're trying to find P, knowing β and P0, in β = 20 log(P/P0).
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 9 ·
Replies
9
Views
11K
Replies
4
Views
2K
  • · Replies 2 ·
Replies
2
Views
14K
  • · Replies 1 ·
Replies
1
Views
18K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
5
Views
2K
  • · Replies 4 ·
Replies
4
Views
5K
Replies
4
Views
2K