Ohm's law, or the Ohm's equation, explains the relationship between current, resistance, and voltage. It states that the amount of current (I) that flows in a circuit is directly proportional to the voltage (V) or potential difference applied to it and indirectly proportional to the resistance (R). It is presented with the following formula: `V = IR` .

The electric current is measured in amperes (A), the potential difference or voltage is measured in volts (V), and the official SI unit of resistance is the ohm (Ω). Both Ohm's law and the unit of electrical resistance are named after the German scientist Georg Ohm.

Ohm's law is one of the most basic and most important laws regarding electrical circuits in physics. Not all electronic devices follow Ohm's law; linear electronic devices, for example, do. The electronic materials and devices that follow Ohm's law, in which the current is directly proportional to the voltage applied, are called ohmic materials or ohmic devices, such as wires or resistors, while those components that don't follow Ohm's law are known as non-ohmic components.

**Further Reading**

**What is Ohm's law?**

Ohm's Law is the relationship between power, current, voltage, and resistance. It was discovered by Georg Simon Ohm. The main idea of his discovery indicated that the amount of electric current that passes through a metal conductor is in direct proportion to the amount of voltage that passes through the conductor.

Power is measured in watts and is the amount of current times the voltage level.

Current can be compared to water flowing down a river. It is what passes through a conductor.

Voltage is the pressure that flows within the current. It is what pushes the current through the conductor.

Resistance is a way to determine how much current will flow through a conductor. If something has a high resistance it will not allow much energy to pass through the conductor.

**What is Ohm's law?**

Ohm's Law relates the electrical resistance of a conductor to the voltage across it and current passing through it.

The modern form of Ohm's law is V = IR, where V is voltage, I is current, and R is the resistance of the cunductor.

The law was named after the German physicist Georg Ohm who in 1827 made measurements of applied voltage and current through simple electrical circuits containing various lengths of wire.

The most common application of Ohm's law is to circuit elements known as resistors. However, the flow of electricity through many complicated objects or systems can be modled as if the electricity were flowing through simple circuit elements, like resistors. Thus Ohm's law finds wide application in electrical sciences.

**What is Ohm's law? **

Ohm's law is one of the most commonly used physics principles. It relates voltage, current and resistance. It can be written as:

V= I x R

It states that the voltage or potential difference across a conductor or between any two points can be determined as the product of current flowing through this conductor (or between the two points) and the resistance offered by the conductor (or all the devices between the two given points).

It can also be written as: I = V/R

and can help us determine the electrical current in a circuit.

A circuit typically has a voltage source, such as a battery, some resistance (offered by the device or wire, etc.). Knowing the voltage generated by the battery and the resistance in the circuit, we can calculate the current flowing through it.

Hope this helps.

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