The sound level at a point is increased by 30 decibels. By what factor is the amplitude increased ?
The bel is defined logarithmically, meaning an increase of 1 bel indicates the amplitude increasing by a factor of 10. Since 10 decibels = 1 bel, an increase of 10 decibels indicates the amplitude increasing by a factor of 10.
Since 30 decibels is 3 lots of 10 decibels, the amplitude is increased by 3 factors of 10, or
In general, an increase of