# Intensity of two sound pressure waves

In summary, the conversation discusses the relationship between intensity and amplitude, with the main focus on understanding the differences between the areas represented in the graphs. The conclusion is that the areas are irrelevant and the comparison should be based on the intensities of the two sources at the same point in space and time. Ultimately, it is determined that wave 2 has a greater intensity than wave 1, and the conversation ends with a thank you for the clarification.
Homework Statement
Ans: C

I tried to use the intensity formulae and after manipulating it got an expression which gave me wrong answer.
It seems the areas are not equivalent somehow, any explanation?
Relevant Equations
I = P/A

Hi @iQadmat and welcome to PF.

How does the intensity depend on the amplitude? You can read the amplitudes of the two waves off the graph and compare.

kuruman said:
Hi @iQadmat and welcome to PF.

How does the intensity depend on the amplitude? You can read the amplitudes of the two waves off the graph and compare.
Hi and thanks for welcoming me!

I know the intensity is directly proportional to amplitude^2 frequency^2 and inversely proportional to radius^2, but my point was the areas (which I showed in ss) are different somehow and I want to understand the differences between them and what they represent.

So far my understanding*
[The initial 'A' is showing the area at which the power from source is acting upon but the final 'A' (later derived from 'F') is not the initial 'A' but is the area of the wave particle which times by pressure of wave equals 'F' .]

Delta2
The areas are irrelevant. This is a comparison of intensities of two different sources at the same point in space and time. If you must, assume that the two sources are at the same distance from two detectors with identical areas. Compare the detectors' readings. Clearly, wave 2 has greater intensity than wave 1. By what factor?

kuruman said:
The areas are irrelevant. This is a comparison of intensities of two different sources at the same point in space and time. If you must, assume that the two sources are at the same distance from two detectors with identical areas. Compare the detectors' readings. Clearly, wave 2 has greater intensity than wave 1. By what factor?
I got it now, Thanks for your help!

Delta2 and kuruman

## 1. What is the definition of intensity in sound waves?

Intensity is a measure of the amount of energy that is transferred by a sound wave per unit of area, per unit of time. It is typically measured in watts per square meter (W/m²).

## 2. How is the intensity of a sound wave related to its amplitude?

The intensity of a sound wave is directly proportional to the square of its amplitude. This means that as the amplitude increases, the intensity also increases.

## 3. What factors affect the intensity of a sound wave?

The intensity of a sound wave is affected by the amplitude of the wave, the distance from the source, and the medium through which the sound is traveling. Other factors such as temperature and humidity can also have an impact on intensity.

## 4. How is the intensity of two sound waves combined?

The intensity of two sound waves can be combined using the principle of superposition. This means that the intensities of the two waves are added together at each point in space, resulting in a combined intensity that is the sum of the individual intensities.

## 5. How is the intensity of a sound wave measured?

The intensity of a sound wave can be measured using a sound level meter, which measures the pressure of the sound wave and converts it to decibels (dB). The higher the decibel level, the higher the intensity of the sound wave.

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