Can low frequency radio waves pass through the human body?
For radio frequency engineering, a really simple model of the human body is salty water, which acts like a lossy conductor. Low frequency radio waves have a long “penetration depth” distance which is actually longer than the distance through your body, so they pass through (with some attenuation depending on the frequency). Higher frequency radio waves have a smaller penetration depth so at a high enough frequency your body absorbs all the energy that enters it. Note that you can think of the “penetration depth” as being similar to “skin depth” in a metal wire carrying an RF signal. Also note that the human body not only absorbs but also reflects radios waves which is why human beings (such as parachute jumpers) show up on radar and also show up on microwave motion detectors in a security system. The RF absorption is different for fat tissue, muscle or bone.
