mystery
The name given to movies with sound during the 1920s was "talkies".
roar
a decibel
"Newsreels"
Growl
Falsetto.
ultrasonic
Drone.
The unit of electrical charge is the coulomb, a special name given to an ampere second.
instrument for measuring sound was named after which scientist?
Sound intensity is a measure of how well a sound can be heard. It quantifies the amount of sound energy passing through a unit area in a given time and is typically measured in decibels (dB).
the loudness of sound is measured in decibels - dB