Archive for February 2016

Electromagnetism- the Secret of Your Storage Drive

Whether you prefer classic hard disk drives or solid-state drives (also called flash drives), you rely on some form of electromagnetism to store your precious data. Your data has to be able to be converted into digital form to be stored in a computer, and as you likely know, digital data is stored in binary code, or a sequence of 0’s and 1’s.

But it’s not as if there’s just a bunch of 0’s and 1’s in your physical hard drive that your computer then configures into the data you recognize when you see it on your monitor. No, the physical way of storing binary code is through either the presence or absence of magnetism or electrical current.

b.opIn the case of a hard disc drive, if there’s no magnetism, that means 0. If there is magnetism, that means 1. A piece of magnetized metal reads the presence or absence of magnetism on tiny (microscopic) units of space on a spinning disk and from that understands what binary code to send to the computer, which then uses software to translate that code into more digestible information for you to read from your monitor.

In the case of a solid state drive, the absence of an electric current means 0, and the presence of an electric current means 1. Because electric currents can be created by transistors and transistors are able to be made smaller and smaller as time goes on (while hard disk drives can only be so ┬ásmall and still be functional due to their reliance on a spinning disk mechanism), solid-state drives are capable of being much smaller and storing the same amount of information as hard disk drives. However, if your SSD fails, it’s going to be way less likely that you’re able to recover the information.

But this give and take between electricity and magnetism goes much deeper than a choice between storage drives. Magnetism actually begets electricity, and the other way around. Here’s how:

It comes down to subatomic particles, as things so often do. Each electron is surrounded by a force called an electric field. When an electron moves, it creates a second field called a magnetic field. When electrons are made to move together, or flow in an electric current through a conductor (i.e. a metal or other substance with a structure that enables electrons to weave through the place comfortably), the conductor becomes a temporary magnet.

hmBut that’s electricity begetting magnetism. How would that current even be forced to be created? If you get a coil of wire and place it near a magnet with an unchanging magnetic filed, nothing happens. However, if that magnetic field is changed by moving the magnet back and forth or spinning the wire, the changing magnetic field can produce an electric current in the wire.

Electricity and magnetism have always been extremely closely related, in an interactive relationship known as electromagnetism. Flowing electrons produce a magnetic field and spinning magnets cause an electric current to flow. Simple as that.