Ohm’s Law

Ohm’s law describes the relationship between voltage (U), current (I) and resistance (R) in an
electrical circuit and is formulated as U = I × R. The law states that the greater the voltage
applied to a resistor, the greater the current that will flow through it. Conversely, a

greater resistance will result in less current at a given voltage.

Ohm’s Law Explained

Voltage (U): The electrical “force” that causes electrons to move. Measured in volts (V).
Current (I): The amount of electric charge passing a point per unit of time. Measured in amperes (A).
Resistance (R): A component’s ability to resist the current. Measured in ohms (Ω).

How the Law is Used

Calculating Voltage (U): If you know the current (I) and the resistance (R), you can find the voltage by multiplying them together: U = I × R.
Calculating Current (I): If you know the voltage (U) and the resistance (R), you can find the current by dividing the voltage by the resistance:
Calculating Resistance (R): If you know the voltage (U) and the current (I), you can find the resistance by dividing the voltage by the current:

Ohm’s Triangle

To remember the three formulas, you can use “Ohm’s Triangle”.

Cover the value you want to find.
If the other two values are next to each other, you multiply them.
If one value is above the other, you divide the top one by the bottom one.

Additional information

Weight	1 g
Dimensions	50 × 5 × 5 mm

Resistor Color Codes

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