Why does electric current produce a magnetic field ?

Electric current produces a magnetic field due to the movement of electric charges. When charges move, they create a disturbance in the electromagnetic field around them, which manifests as a magnetic field.

Here’s a more detailed explanation:

Moving Charges and Magnetic Fields: According to Ampère's Law, a magnetic field is generated in the space surrounding a current-carrying conductor. This happens because electric current consists of moving electrons, which are charged particles. The movement of these charges creates a magnetic field in a direction that is perpendicular to the direction of the current.

Electromagnetic Field Theory: In classical electromagnetism, described by Maxwell's equations, electric and magnetic fields are interrelated. A changing electric field creates a magnetic field, and a moving charge (current) inherently involves a changing electric field, thus generating a magnetic field.

Right-Hand Rule: The direction of the magnetic field relative to the current can be determined using the right-hand rule: if you point the thumb of your right hand in the direction of the current, the fingers curl in the direction of the magnetic field around the conductor.

This phenomenon is fundamental to electromagnetism and underlies the operation of many electrical devices, such as electromagnets, electric motors, and transformers.