O'Reilly logo

Consumer Electronics by S. P. Bali

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

SOUND LEVEL

The reference intensity level of 10–12 W/m2 is a typical value for the threshold of human hearing. A sound of intensity I0 has a sound level of 0 dB, while a sound at the upper range of human hearing, called the threshold of pain, has an intensity of 1 W/m2 and a sound level of 120 dB. Thus the human ear is capable of responding to intensities ranging over 12 orders of magnitude on a logarithmic scale of intensity called sound level, SL.

Example 1.5 The intensity of waves at a distance of 20 m from their source is 25 W/m2. What is the intensity at a distance of 50 m and how do the amplitudes of the waves compare at the two places?

Solution

 

 

The amplitudes are in the inverse ratio of the distances from the sources.

 

 

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required