Physics Magnetic Effects of Current and Magnetism Syllabus for NEET 2026

The connection between Electricity and Magnetism explains many important physical phenomena observed in electrical systems and magnetic devices. When electric current flows through a conductor, it creates a magnetic field around it, leading to interactions between charges, currents, and magnets.

This unit focuses on magnetic fields produced by electric currents, force on moving charges and conductors, magnetic dipoles, and magnetic properties of materials. It also introduces important applications such as galvanometers, solenoids, and magnetic field-based devices used in Physics and engineering.

Magnetic Field Due to Current and Biot–Savart Law

A current-carrying conductor produces a magnetic field in the surrounding region. The direction of the field can be determined using the right-hand thumb rule.

Biot–Savart law gives the magnetic field produced by a small current element at a point in space. This law helps in calculating magnetic fields due to current-carrying circular loops and other conductor arrangements.

The strength of the magnetic field depends on the magnitude of the current, the distance from the conductor, and the geometry of the current path.

Ampere’s Law and Magnetic Force

Ampere’s Circuital Law relates the magnetic field around a closed path to the current enclosed by that path. It is useful for calculating magnetic fields produced by long straight conductors and solenoids.

This unit also explains the force experienced by:

• Moving charges in electric and magnetic fields

• Current-carrying conductors placed in magnetic fields

The interaction between two parallel current-carrying conductors leads to the definition of the ampere.

Magnetic force plays an important role in electric motors, moving charges, and electromagnetic devices.

Torque on Current Loop and Moving Coil Galvanometer

A Current Loop placed in a magnetic field experiences torque due to the interaction between the magnetic field and the current.

This principle is used in the moving coil galvanometer, which detects and measures small electric currents. It also explains the sensitivity of the galvanometer and its conversion into:

• Ammeter

• Voltmeter

Understanding torque on current loops also helps in studying magnetic dipole behaviour.

Magnetic Dipole and Bar Magnet

A current loop behaves like a magnetic dipole and possesses a magnetic dipole moment. Similarly, a bar magnet can be considered equivalent to a current-carrying solenoid.

It explains magnetic field lines produced by bar magnets and magnetic dipoles along:

• Axial position

• Equatorial position

A magnetic dipole placed in a uniform magnetic field experiences a torque that tends to align it along the magnetic field direction.

Magnetic Properties of Materials

Different substances respond differently when placed in a magnetic field.

Diamagnetic substances weakly repel magnetic fields, paramagnetic substances weakly attract them, while ferromagnetic substances show very strong attraction and permanent magnetic behaviour.

It also explains how temperature affects magnetic properties, especially in ferromagnetic materials, where magnetism decreases at high temperatures.

Magnetic Effects of Current and Magnetism: Complete Study Resources By PW

Regular formula revision and understanding of magnetic field diagrams are important for preparing for this unit well. PW study resources for Magnetic Effects of Current and Magnetism are given here: