Ohm's Law


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. Ohm's Law is shown below.

I = V/R,
I = current, V = voltage, and R = resistance

*Depending on what you are trying to solve we can rearrange it two other ways.
V = I x R
R = V/I

*All of these variations of Ohm’s Law are mathematically equal to one another.

In the first version of the formula, I = V/R, Ohm's Law tells us that the electrical current flowing in a circuit is directly proportional to the voltage and inversely proportional to the resistance.
In other words, an increase in the voltage will tend to increase the current while an increase in resistance will tend to decrease the current.

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