Why are humans not able to see,feel or hear radio waves? We are sensitive to the rest of the waves in the EM spectrum. If EM waves are composed of oscillating magnetic and electric fields, why am I not electrocuted by the electric constituent of the Radio waves?
In: Physics
As others have said, radio waves with enough power and proximity will heat our internal tissue which is considered dangerous. There is a maximum permissible exposure (MPE) that you can calculate based on frequency, power density, proximity, and duty cycle (how long the radio is transmitting for). Some more reading here: https://www.fcc.gov/general/radio-frequency-safety-0
As an example, many 5 watt VHF handheld transceivers used in amateur and marine radio technically exceed the MPE if you hold the radio up to your face while talking – even with a modest duty cycle. Thus, current recommendations suggest using an external mic with the radio.
Cellphones have a power density measured in milliwatts so even with a large duty cycle and close proximity they never get close to a humans MPE.
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