Enter two values to calculate the third.
Calculating Ohmic resistance is a fundamental task in electronics and electrical engineering. This is due to the universal law known as Ohm's Law, which describes the relationship between current, voltage, and resistance in an electrical circuit.
Ohm's Law states that the current (I) flowing through a conductor (like a wire) between two points is directly proportional to the voltage (V) across the two points, and inversely proportional to the resistance (R) between them. This is commonly expressed in the formula V=IR.
From this, it follows that, if we know the voltage and current, we can calculate the resistance by dividing the voltage by the current. This gives us
R = V / I
In the same spirit, if we know the resistance and the current, we can calculate the voltage by multiplying the current by the resistance. This gives
V = I * R
Finally, if we know the voltage and the resistance, we can calculate the current by dividing the voltage by the resistance, giving us
I = V / R
When calculating Ohmic resistance, or any of the other values in Ohm's Law, it's important to remember that this law only applies to materials that behave Ohmically - that is, their resistance does not change at different levels of current or voltage. This is the case for many materials, but not all. Some materials, like semiconductors, have a non-linear V-I characteristic, meaning their resistance varies depending on the applied voltage.