Naval sonar systems work like acoustic floodlights, sending sound waves through ocean waters for tens or even hundreds of miles to disclose large objects in their path. But this activity entails ...
A sound wave is a vibration that travels through a solid, liquid or gas such as the air or water. A loud sound has a large amplitude, a high pitched sound has a high frequency. Musicians and ...
By combining ultrasound with a concept called nonlinear acoustics, you can create sound that stays silent until it reaches a specific location.