I have always been a sucker for romantic movies or novels simply because what they often portray is quite far from what is obtainable in real life. People addicted to romantic literature or movie genre are often hopelessly romantic and finds it hard to face real life that is filled with twists and turns. However, I cannot say the same for science fiction, be it in movies or literature.
The reason is not far fetched. Hardly will anyone see a science fiction movie or novel in which what is portrayed as science is far from reality. For example, no one tells you that pure water has the ability to become an acid just by placing it in the air overnight. There are always a few real-life applicable lessons to learn in SciFi series for those that are science-oriented.
A few days ago, a friend of mine explained how he got to learn about Faraday shield through a movie. In the movie, an improvised electronic device (IED) was set to be detonated in a particular area within New York City. Fortunately, the FBI was able to detect the location of the device but the challenge remained how to defuse the structure.
After trying all possible means without success, a Radiation Oncologist then suggested that they stop the likely remote activation of the bomb using a Faraday cage or a Faraday shield. A Radiation Oncologist is medical personnel who is a specialist in treating cancer using ionizing radiations. Who could have known that a Doctor would be a hero for the day!
A Faraday cage is a container made of conducting material, such as wire mesh or metal plates, that shields what it encloses from external electric fields. source
The suggestion seemed plausible but there was an urgent need to get an improvised structure to be used as the shield since a standard one could not be obtained nearby within a short span of time required before the explosive is set off. Just as they were contemplating on what to do next, the Oncologist noticed a kaput microwave oven lying on the ground nearby.
She immediately picked the microwave oven up and placed it on the IED. The Jihadists that happen to be the perpetrator of the evil tried to detonate the IED from their location a few minutes after but to their chagrin, they could not get a signal through. That was how the FBI was able to save thousands of people from the throes of an IED even without their knowledge.
Could it be true that a microwave oven can serve as a Faraday shield?
This is exactly what the friend of mine tried to prove after finishing with the movie. He needed to show that a microwave oven has the capacity to prevent electromagnetic waves from getting into it. Although there was no explosive for demonstration, he was armed with a mobile phone and his wireless router. The router acts as a mobile wifi hotspot through which phones are able to access the internet.
He powered on the router and placed it in an oven (the oven is not connected to power) and then tried to connect to the router's wifi with his mobile phone. As expected, the wifi signal has been completely shut off.
Through the transparent door of the microwave oven, he noticed that even though the router could not send wifi signals out to the mobile phone, it was still able to receive network signals from the service provider. This thus means that the unpowered oven still has the capacity to admit some waves (high frequencies?).
Out of his inquisitiveness, he decided to take the experiment a little step further. with the router still inside the microwave oven, he powered on the oven for about two minutes and then observed the router if it is still able to receive network signal from the provider. At this point all the network signals had completely been shut off.
Lessons learnt
With the demonstration, it is shown that microwave ovens can act as Faraday shields to a particular degree when not powered, and they even act at a higher degree when powered on. The extent to which they are able to shut off signals depends on the frequency of the wave or signal with radio waves being especially susceptible.
I will love to read the contributions of those that are specialists in this field. What do you guys think?
Resources
- https://en.wikipedia.org/wiki/Electromagnetic_radiation
- https://backyardbrains.com/experiments/faraday
Credit: Olakunle Excel