# Finding the amplitude of a pressure wave

• Patdon10
In summary, the sound level in decibels is typically expressed as β = 10 log(I/I0) and can also be expressed in terms of a pressure difference as β = 20 log(P/P0), where P0 is the smallest pressure difference noticeable by the ear: P0 = 2.10^-5 Pa. To find the amplitude of the pressure wave generated by a loud rock concert with a sound level of 106 dB, you need to solve for P in the equation β = 20 log(P/P0), using the given values for β and P0.
Patdon10

## 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.

## 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?

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).

## 1. How is the amplitude of a pressure wave defined?

The amplitude of a pressure wave is defined as the maximum displacement or distance that the wave moves away from its equilibrium point.

## 2. What units are used to measure the amplitude of a pressure wave?

The amplitude of a pressure wave is typically measured in units of pressure, such as pascals (Pa) or atmospheres (atm).

## 3. How is the amplitude of a pressure wave related to its energy?

The amplitude of a pressure wave is directly proportional to its energy, meaning that the higher the amplitude, the greater the energy of the wave.

## 4. Can the amplitude of a pressure wave change over time?

Yes, the amplitude of a pressure wave can change over time due to factors such as interference, absorption, and reflection.

## 5. How can the amplitude of a pressure wave be measured in a laboratory setting?

The amplitude of a pressure wave can be measured using a pressure sensor or gauge, which can detect changes in pressure caused by the wave.

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