The relationship between Current through and Voltage across a conductor was first discovered by a German scientist George Simon Ohm. This relationship is called Ohm’s Las and be stated as;
The Current “I” flowing through a conductor is directly proportional to the potential difference i.e. Voltage “V” across its ends provided the physical conditions (i.e. temperature, strain, etc) do not change.
In other words;
In any electric circuit, the Current “I” is directly proportional to the applied Voltage “V” and inversely proportional to the total circuit Resistance “R” if the physical condition of the circuit remain unchanged i.e. (Temperature of the circuit does not change)
I∝V or V/I = Constant = R
Where “R” is a Constant of proportionality and is called Resistance of the Conductor.
Current = Potential Difference / Resistance
I = V / R
Good to know
For calculation and simplifying of electric circuits (measuring of Current, Voltage and Resistance), we can use Ohm’s law in the following three forms
I = V/R
R = V/I or
V = IR
Better funny explanation of Ohm’s Law
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Or another funny way to explain Ohm’s Law
If the apply Voltage across a Circuit is 50V, and a series connected Resistor in the circuit which resistance is 10 Ω, then what would be the Current in that Circuit?