• Ohm's Law - calculation and formulas •

Input:
resistance R
 ·
ohms		  
current I

amperes
Output:
voltage V

volts
voltage V
 /
volts		 resistance R

ohms		 current I

amperes
voltage V
 /
volts		 current I

amperes		 resistance R

ohms
V = R × I         I = V / R         R = V / I

The formulas of ohm's law

Ohm's law knows three formulas for calculating the current, the resistor, and the voltage:
If a current I should flow through a resistor R, the voltage V (U) can be calculated.
Formula - voltage
If there is a voltage V (U) at a resistor R, a current I flows through the resistor R.
Formula - current
If a current I flows through a resistor R, there will be a voltage V (U).
Formula - resistance

Name Unit Sign
E volt V
I ampere A
R ohm Ω
P watt W

Tip: The magic triangle

The magic triangle The magic triangle can be used to calculate all formulas of ohm's law.
You hide with a finger the value to be calculated. The other two values
show then how to do the calculation. U = V.

If you need the unit of power P = V × I go to the program:
Calculation: electrical voltage, current, resistance, and power

The symbol I comes from "International Ampere" and R from "Resistance", and U (= V or E)?

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