The electromagnetic waves we use to make wireless calls are integral to our surroundings — and I’m not just talking about visible light. Electromagnetic waves of other frequencies, which we are unable to detect with our eyes, are coming at us from the entire Universe, most intensely from the Sun. The first to deal with wireless energy transmission was Nikola Tesla but the first radio transmission was made by Guglielmo Marconi (in principle, he did the same thing as Tesla but not with the goal of transmitting energy, but information). Thanks to them, we have been able to communicate wirelessly since the end of the 19th century.
Like any technology, telecommunications has undergone dramatic development, which is also evidenced by the mobile phone. Mobile phones are transmitters of specific electromagnetic waves (1,800 MHz — GSM band; 2,100 MHz 3G networks and LTE), which have a maximum power limit of 1 W. If we want to solve the effect of the mobile phone on the human organism, we have to work with the given values. First I will focus on the frequency. When an electromagnetic wave passes through a material, the following fundamental situations can occur — the wave is reflected, passes through, or is absorbed.
The fact that the wave only passes through the environment (for example our brain) means that its energy does not affect the environment in any way. The same is the case when it is reflected from the environment. The problem is when it is absorbed by the material — this will transfer the energy of the wave to the environment (the brain). The critical one here is the 2.45 GHz frequency, which is the frequency that water absorbs (that’s why a microwave works at that frequency). If mobile phones worked at this frequency, they would heat our brains (but thus would not spread further through the head because they would be absorbed and therefore we would not have a signal).
So, from this point of view, the mobile phone is quite safe. Another quantity is power — that is, how many Joules per second the phone emits in the form of electromagnetic waves. As I mentioned above, the maximum limit is 1 W. Which corresponds to the power of an ordinary LED flashlight. Probably none of us have registered a problem when someone shines a similar battery on them (I don’t mean in the eyes, of course). If I add another parameter of the microwave oven — that is, its power, which is 800 W, it is clear that the power of the mobile phone is negligible compared to its power. I greatly simplified the answer (especially with regard to the effect of frequency on the human body), various health organizations dealt more comprehensively with the effect of mobile phones on human health (with the same results).
And finally, I would like to point out that the answer is only focused on the effect of electromagnetic waves from a mobile phone on a person and not on the effects that the use of a mobile phone has on a person's health in general (accidents while talking on the phone while driving, psychological problems, etc.).
Want to ask something?
Send us an e-mail with the subject “Physics mysteries” to the address:
We can't wait to tackle your interesting questions!