Ohm's law means that in the same circuit, the current passing through a conductor is directly proportional to the voltage at both ends of the conductor and inversely proportional to the resistance of the conductor. This law was put forward by georg simon ohm, a German physicist, in his paper Determination of the Law of Metal Conductivity published in April 1826.

With the development of circuit research, people gradually realize the importance of ohm's law, and ohm's reputation is greatly improved. In order to commemorate ohm's contribution to electromagnetism, the unit of resistance is named ohm in physics, which is represented by the symbol ω.

A brief history of the development of physical ohm's law

The first stage of ohm experiment is to explore the relationship between the electromagnetic force attenuation caused by current and the length of wire. The results were published in his first scientific paper 1825 in May. In this experiment, he met with the difficulty of measuring the current intensity.

Inspired by the galvanometer invented by German scientist Schveger, he combined Oster's discovery of current magnetic effect with Coulomb torsion balance method, designed a current torsion balance, and used it to measure current intensity. Ohm comes from preliminary experiments, and the electromagnetic force of current is related to the length of conductor. This relationship is not directly related to today's ohm's law expression. Ohm did not relate the potential difference (or electromotive force), current intensity and resistance at that time.