Mission SM3 Sound Intensity and DeciBel Levels
Hold down the T key for 3 seconds to activate the audio accessibility mode, at which point you can click the K key to pause and resume audio. Useful for the Check Your Understanding and See Answers.
The table at the right lists several sounds and their typical deciBel level. Based on this listing, one would conclude that the sound of normal conversation is ____ times more intense than the sound of a mosquito buzzing.
Every sound intensity has a unique deciBel rating. The deci of deciBel is a Greek prefix similar to the more familiar milli-, centi- and kilo- which commonly precedes units such as liter, gram and meter (for example, centimeter and kilogram). There are 10 deciBels in 1 Bel so the Greek prefix decimeans 1/10-th. The deciBel rating of a sound is 10 times the Bel rating of the sound. The Bel rating of a sound is the number of times greater that it's intensity is than the intensity of the threshold of hearing (1.0 x 10-12 W/m2) - expressed as a power of 10. See Math Magic section.
If one sound is 101 times more intense than a second sound, then its Bel rating is 1 Bel higher and its deciBel rating is 10 deciBels higher.
If one sound is 102 times more intense than a second sound, then its Bel rating is 2 Bels higher and its deciBel rating is 20 deciBels higher.
If one sound is 103 times more intense than a second sound, then its Bel rating is 3 Bels higher and its deciBel rating is 30 deciBels higher.
If one sound is 104 times more intense than a second sound, then its Bel rating is 4 Bels higher and its deciBel rating is 40 deciBels higher.
