Magnetism and Matter

A bar magnet has two poles

A bar magnet has two poles - north and south - that cannot be isolated. When freely suspended, it aligns north-south. Like poles repel, unlike poles a

Magnetic field lines form continuous closed

Magnetic field lines form continuous closed loops, unlike electric field lines. They emerge from the north pole and enter the south pole externally, c

The net magnetic flux through any

The net magnetic flux through any closed surface is zero: ∮B·dS = 0. This reflects the non-existence of magnetic monopoles - magnetic field lines are

A magnetic dipole in uniform field

A magnetic dipole in uniform field B experiences torque τ = m × B but zero net force. The potential energy is U = -m·B, minimum when aligned with fiel

Magnetization M is net magnetic moment

Magnetization M is net magnetic moment per unit volume. Magnetic intensity H represents external field contribution. Total field B = μ₀(H + M). For li