The loudness of a sound is related to the amount of energy that creates the wave and the amount of energy that is then carried by the sound wave. Intensity is another name for loudness. As more energy is put into creating the sound (i.e. the harder you pluck a string or hit a drum), the greater will be the intensity of sound and the higher the decibel level will be. Every 10 decibels increases the energy of the sound by 10 times. So if you go from 10 to 20 decibels, the volume doesn’t double - it increases by 10 times. 30 decibels is 100 times louder than 10 decibels. When energy is used to create the vibration resulting in a sound wave, the loudness of the sound is related to the amplitude of the wave. The more energy that is used, the greater the amplitude of the resulting sound wave, and the louder the resulting sound. Remember, the amplitude of the wave is the height of the wave from the mid-line to the crest. It is difficult to show amplitude and wavelength in a compression wave, but the concept is the same.
Intensity
If a babbling brook is 40 db and a shower is 70 dB, how many times louder is the shower?
1,000 times louder
