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The Landing School
These links are maintained by the NDT, Nondestructive Testing, at Iowa State University.
"Probably the most important mathematical relationship between voltage, current and resistance in electricity is something called “Ohm’s Law”. A man named George Ohm published this formula in 1827 based on his experiments with electricity. This formula is used to calculate electrical values so that we can design circuits and use electricity in a useful manner." (from the site)
"AC is short for alternating current. This means that the direction of current flowing in a circuit is constantly being reversed back and forth. This is done with any type of AC current/voltage source." (from the site)
"DC, or direct current means the electrical current is flowing in only one direction in a circuit. Batteries are a good source of direct current (DC)." (from the site)
Explanation of how electrons and protons react. Scroll down to see an animated diagram.
Ohm's Law - DC
DC Currents - Explanation and a place to enter data for any two quantities to determine the third.
Voltage : Current/Amperage : Power : Resistance
DC Supply Symbol
AC Supply Symbol
Basic Boat Wiring - Solar