Numford

MagnetismClass 12, Magnetism and Matter

Dimensional formula of Magnetic susceptibility

[M0 L0 T0]

Symbolχ SI unitnone, a pure number

Magnetisation divided by the magnetising field, a pure number.

Derivation

How to get the dimensional formula of magnetic susceptibility

  1. Start from the definition: magnetic susceptibility = magnetisation / magnetic field strength.
  2. area = length × length, so area is [L] × [L] = [L2].
  3. magnetic moment = electric current × area, so magnetic moment is [A] × [L2] = [L2 A].
  4. volume = length3, so volume is [L]3 = [L3].
  5. magnetisation = magnetic moment / volume, so magnetisation is [L2 A] / [L3] = [L-1 A].
  6. velocity = length / time, so velocity is [L] / [T] = [L T-1].
  7. acceleration = velocity / time, so acceleration is [L T-1] / [T] = [L T-2].
  8. Put in the dimension of each part: [L-1 A] / [L-1 A].
  9. Add the powers of each base quantity: [M0 L0 T0].
Same dimensions

Quantities with the dimensions [M⁰ L⁰ T⁰]

Equal dimensions do not make them the same quantity. Compare magnetic susceptibility with the others in the full grid.

Practice

Three questions on magnetic susceptibility

1Which of these has the same dimensions as magnetic susceptibility?

2Which of these has no dimensions at all?

3Which one has different dimensions from the others?

Questions

Magnetic susceptibility: quick answers

What is the dimensional formula of magnetic susceptibility?

The dimensional formula of magnetic susceptibility is [M⁰ L⁰ T⁰]. It comes from magnetic susceptibility = magnetisation / magnetic field strength.

What is the SI unit of magnetic susceptibility?

Magnetic susceptibility has no unit, because it is a pure number.

Is magnetic susceptibility dimensionless?

Yes. Magnetic susceptibility is a ratio of like quantities, so every power in its dimensional formula is zero: [M⁰ L⁰ T⁰].

Open the dimensional formula tool