How is the magnetic field inside a long straight wire calculated?

The magnetic field inside a long straight wire is calculated using the Biot-Savart Law.

To calculate the magnetic field inside a long straight wire, we use the Biot-Savart Law. This law states that the magnetic field at a point in space due to a current-carrying conductor is proportional to the current and the length of the conductor, and inversely proportional to the distance from the point to the conductor.

Mathematically, the Biot-Savart Law can be expressed as B = μ0I/2πr, where B is the magnetic field at a point, I is the current in the wire, r is the distance from the point to the wire, and μ0 is the permeability of free space.

When calculating the magnetic field inside a long straight wire, we assume that the wire is infinitely long and has a uniform current density. In this case, the magnetic field is constant and has a magnitude given by B = μ0I/2πr.

It is important to note that the direction of the magnetic field inside the wire is determined by the right-hand rule. If you wrap your right hand around the wire with your thumb pointing in the direction of the current, your fingers will curl in the direction of the magnetic field.

Overall, the Biot-Savart Law provides a useful tool for calculating the magnetic field inside a long straight wire, which is an important concept in the study of electromagnetism.