Amplitude of sound wave in by 50%

In summary, the increase in decibel level for a 50% increase in vibration amplitude is approximately 1.8db.
  • #1
hemetite
50
0
Any kind soul to help me with this questions...i am stuck

qn. The amplitude of vibration of a certain sound wave is increase by 50%. What is the corresponding increase in the decibel level of the sound?

My attempt..

beta= 10 log ( I/Io)

lets just take I = 2.0 x 10^-7
let just take Io= 1.00 x 10^-12

then 10 log( 2.0 x 10^-7/1.00 x 10^-12) = 10 log (2.0 x 10^5) = 53db

if we increse I by 50 % = (2.0 x 10^-7) x 1.5
= 3.0 x 10^-7

then
10 log( 3.0 x 10^-7/1.00 x 10^-12) = 10 log (3.0 x 10^5) = 54.8 db

so the change of decibel = 54.8db - 53db = 1.8db

correct attemp this question this way??
 
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  • #2
hemetite said:
Any kind soul to help me with this questions...i am stuck

qn. The amplitude of vibration of a certain sound wave is increase by 50%. What is the corresponding increase in the decibel level of the sound?

My attempt..

beta= 10 log ( I/Io)

lets just take I = 2.0 x 10^-7
let just take Io= 1.00 x 10^-12

then 10 log( 2.0 x 10^-7/1.00 x 10^-12) = 10 log (2.0 x 10^5) = 53db

if we increse I by 50 % = (2.0 x 10^-7) x 1.5
= 3.0 x 10^-7

then
10 log( 3.0 x 10^-7/1.00 x 10^-12) = 10 log (3.0 x 10^5) = 54.8 db

so the change of decibel = 54.8db - 53db = 1.8db

correct attemp this question this way??

Since the increase is by a factor of 50% you can also express the increase
as simply 10log10(1.5) = 10*(0.176) = 1.76 db
 
  • #3



I would like to clarify that the decibel level of a sound wave is determined by its intensity, not its amplitude. The intensity of a sound wave is directly proportional to the square of its amplitude. Therefore, increasing the amplitude of a sound wave by 50% would result in a 125% increase in its intensity, not just 50%.

To calculate the corresponding increase in decibel level, we can use the following formula:

β2 = β1 + 10 log (I2/I1)

where β2 is the new decibel level, β1 is the initial decibel level, I2 is the new intensity, and I1 is the initial intensity.

Using your example, if the initial intensity is 2.0 x 10^-7 and we increase it by 50%, the new intensity would be 3.0 x 10^-7. Plugging these values into the formula, we get:

β2 = 53 + 10 log (3.0 x 10^-7/2.0 x 10^-7) = 53 + 10 log (1.5) = 53 + 1.8 = 54.8 db

Therefore, the corresponding increase in decibel level would be 54.8 dB - 53 dB = 1.8 dB, which is the same as your calculation. However, it is important to note that the increase in decibel level is not directly proportional to the increase in amplitude, but rather to the increase in intensity.

I hope this explanation helps to clarify any confusion and aids in your understanding of sound waves and decibel levels. If you have any further questions, please feel free to ask.
 

1. What does "amplitude of sound wave in by 50%" mean?

Amplitude refers to the maximum displacement of particles within a sound wave. When we say "amplitude of sound wave in by 50%", it means that the amplitude has decreased by 50% compared to its original value.

2. How is the amplitude of a sound wave measured?

The amplitude of a sound wave is typically measured in units of decibels (dB). This is a logarithmic scale that represents the intensity or loudness of a sound wave.

3. What causes a change in the amplitude of a sound wave?

The amplitude of a sound wave can change due to various factors, such as distance from the source of the sound, absorption by the medium through which the sound is traveling, or the frequency of the sound wave.

4. How does a 50% decrease in amplitude affect the perception of sound?

A 50% decrease in amplitude can result in a significant decrease in the loudness or volume of the sound. This can make the sound appear fainter or quieter to our ears.

5. Can the amplitude of a sound wave be increased or decreased intentionally?

Yes, the amplitude of a sound wave can be intentionally increased or decreased through various methods, such as adjusting the volume on a speaker or using amplifiers to increase the signal strength of the sound wave.

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