Induction
When a shark swims through the Earth's magnetic field, electromagnetic induction – phenomena which generates an electric field as charged particles move through a magnetic field – creates an electric field around the shark. Minute differences in the Earth's magnetic field at different locations result in minute differences in the induced electric field which may be detected by the shark's sensitive electroreceptors, especially as the head region moves back and forth during swimming (Lohmann and Johnsen 2000).
The law of electromagnetic induction (Faraday's law of induction) states that induced electromotive force (EMF) is proportional to the rate of change of the magnetic flux through a coil (an electric current can also be produced within a conductor when the conductor is moved through a magnetic field). This occurs because the force generated by the magnetic lines is applying a force on the free electrons in the conductor, causing the electrons to move.
Read more about this topic: Magnetic Shark Repellent
Famous quotes containing the word induction:
“They relieve and recommend each other, and the sanity of society is a balance of a thousand insanities. She punishes abstractionists, and will only forgive an induction which is rare and casual.”
—Ralph Waldo Emerson (1803–1882)
“One might get the impression that I recommend a new methodology which replaces induction by counterinduction and uses a multiplicity of theories, metaphysical views, fairy tales, instead of the customary pair theory/observation. This impression would certainly be mistaken. My intention is not to replace one set of general rules by another such set: my intention is rather to convince the reader that all methodologies, even the most obvious ones, have their limits.”
—Paul Feyerabend (1924–1994)