Why do Faraday Cages work?

Electricity is the lifeblood of many aspects of our world. Without volts and amps, many of our technological innovations would cease to exist. Even our bodies wouldn't function without an electrical charge zipping through our cells. But what electricity gives, electricity can take away. read more

As a Faraday cage distributes that charge or radiation around the cage's exterior, it cancels out electric charges or radiation within the cage's interior. In short, a Faraday cage is a hollow conductor, in which the charge remains on the external surface of the cage. read more

That's because the aluminum hull of the plane creates a Faraday cage. The charge from the lightning can pass harmlessly over the surface of the plane without damaging the equipment or people inside. It's not shocking, really. read more

Faraday cages cannot block stable or slowly varying magnetic fields, such as the Earth's magnetic field (a compass will still work inside). To a large degree, though, they shield the interior from external electromagnetic radiation if the conductor is thick enough and any holes are significantly smaller than the wavelength of the radiation. read more