Ohms law is named after German Physicist Georg Ohm. He wrote a treatise on electrical currents passing through wires and created some equations that would eventually become Ohms law. But what does Ohms law actually relate to?
The first element of Ohms law is voltage, often abbreviated to the letter V. You will sometimes also see it signified by the letter E, which stands for electromotive force. Voltage is measured in units called volts.
Voltage is probably the most difficult to understand of the three components of Ohms law. In essence, it is a measurement of the strength of a power source to push electricity around a circuit.
The higher the voltage, the stronger the push. So for instance, a battery might have a voltage of 1.5 V. In comparison, a 3 V battery would have twice the strength to push electricity around the circuit.
Current is most easily described as the flow of electricity around a circuit. Current is measured in units called amperes, or amps. In Ohms law, it is represented by the letter I.
The larger the push from the power source (and therefore the larger the voltage) the more current will flow around the circuit. As you would imagine, if you double the amount of voltage, you will double the amount of current.
The final part of Ohms law is resistance. Resistance is measured in units called Ohms, named after (you guessed it) our friend Georg again. In Ohms law, resistance is represented by the letter R.
Resistance (not to be confused with resistivity) is basically a measurement of how hard it is to get current to flow around the circuit. It has a different value for different materials - the more easily current can flow through a material, the lower the resistance.
The length and thickness of a wire will also affect resistance. It is harder for the current to flow through a thin wire than a thick one.