radiation
yes
Overheating.
The sun.
sound waves with frequencies 20 hertz or lower are infrasonic and waves above 20,000hertz are ultra sonic!
there are many dangers but the main ones are cancer lukemia and disformation of a new born child
it is used for waves sounds as well
Ultra sonic waves are a sound frequency that is oftentimes silent to humans. Research shows there is no long term negative affects due to exposure to these sounds.
C ultra violet light
Box jellyfish, Sharks, Rips and strong waves
phones, airoplaines, lawn mowers
IT DETECT IT BY ULTRA VIOLET RAYS.