## What is Magnetic Moment?

**Magnetic moment** is a determination of its tendency to get arranged through a magnetic field. As we all know, a magnet has two poles, i.e., **North** and **South**. The distance between these two poles of a magnetic or a magnetic dipole is named as the magnet length and is given as the 2 ιι. If **m** is the power of any magnetic pole then the magnets magnetic dipole moment is provided by the vector **M** and it is articulated as

Where, m = Strength of any magnetic dipole

ιι = Magnet length.

## Magnetic Moment Units

In the definition for current loop, the Magnetic moment is produce of current flowing and the area,

**M = I A**

So the unit conferring to this definition is articulated by **Amp-m ^{2}**.

It can also be suggested in terms of torque and moment. Conferring to that, the torque is measured in Joules **(J)** and the magnetic field is measured in tesla **(T)** and thus the unit is **J T ^{-1}**.

So, these two units are equivalent of each other and is provided by** : 1 Amp-m ^{2} = 1 J T^{ -1}.**

## Magnetic Dipole Moment

A Magnetic Dipole comprises of two unlike poles of equivalent strength and parted by a small distance.

For instance : The needle of a compass, a bar magnet, etc. are the magnetic dipoles. We shall show that a current loop works as a magnetic dipole.

Magnetic Dipole Moment is described as the product of pole strength and the distance amidst the two poles. The distance between the two poles of a magnetic or a magnetic dipole is named as the magnet length and is given as the 2 ι.

If **m** is the power of any magnetic pole then the magnetic dipole moment of the magnet is signified by the vector **M** and it is represented as

The Magnetic dipole moment is a vector as termed above and it has direction from the South Pole of the magnet to the north pole of the magnet as presented in the fig

## Expression for Magnetic Dipole Force:

The force on a magnetic dipole is because of both the poles of the magnet and we consider the magnetic dipole of a bar magnet and assume that the magnet is kept in a unbroken magnetic field **B**. In that situation, the force on the separate poles is articulated as

**m _{B}** which is along the magnetic field

**B**= Force on the N-pole

**m _{B}** and this is opposite to magnetic field

**B**= Force on the S-pole

These forces are equivalent in magnitude, but opposite in direction and they form a parallel couple which rotates the magnet clockwise and creates a net torque on the magnet because of the individual force in a couple thus we have torque acting on the bar magnet.

τ = Moment of the couple.

τ = m_{B} × 2L sin θ

Where θ is the angle amid the magnet and the magnetic field therefore from the above discussion we have

M = m x 2L

Thus, Magnetic dipole moment is articulated by

ττ = MB sin θ

In vector form, it can be rephrased as

τ = M × B.

This is the required expression for the magnetic dipole force.

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