Magnetism and Matter

• Arc Length = L = Rθ (θ=π/3). Chord Length L' = 2Rsin(θ/2) = 2Rsin(π/6) = R. Since R = L/θ = 3L/π, the new magnetic length is L' = 3L/π.
• New Moment M' = m × L' = m × (3L/π). Substitute m = M/L. M' = (M/L) × (3L/π) = 3M/π.

(NEW NCERT 12^th Page No. 137, 138)

Relative magnetic permeability (\(\mu_r\)) is a measure of how much a material can become magnetized in an applied magnetic field compared to vacuum. When \(\mu_r \gg 1\), it indicates that the material is highly magnetic, typically found in ferromagnetic materials. Examples of substances with \(\mu_r \gg 1\) include iron, cobalt, and nickel.

• Magnetic potential energy U = – m ⋅ B = –mB cosθ.
• m is perpendicular to B, so θ = 90°.
• U = –mB cos(90°) = –mB * 0 = 0.

  (NEW NCERT 12^th Page No. 137, 138, 139, 140, 141)

For diamagnetic substances $\chi <0$

small and negative

Relative magnetic permeability (\(\mu_r\)) is a measure of how much a material can become magnetized in an applied magnetic field compared to vacuum. When \(\mu_r \gg 1\), it indicates that the material is highly magnetic, typically found in ferromagnetic materials. Examples of substances with \(\mu_r \gg 1\) include iron, cobalt, and nickel.

For diamagnetic substances $\chi <0$

small and negative

Paramagnetic materials have unpaired electrons, which allows them to be weakly attracted to a magnetic field. Sodium and Calcium both have unpaired electrons in their outer shells, making them paramagnetic.

Relative magnetic permeability (\(\mu_r\)) is a measure of how much a material can become magnetized in an applied magnetic field compared to vacuum. When \(\mu_r \gg 1\), it indicates that the material is highly magnetic, typically found in ferromagnetic materials. Examples of substances with \(\mu_r \gg 1\) include iron, cobalt, and nickel.

Paramagnetic materials have unpaired electrons, which allows them to be weakly attracted to a magnetic field. Sodium and Calcium both have unpaired electrons in their outer shells, making them paramagnetic.

Paramagnetic materials have unpaired electrons, which allows them to be weakly attracted to a magnetic field. Sodium and Calcium both have unpaired electrons in their outer shells, making them paramagnetic.

Relative magnetic permeability (\(\mu_r\)) is a measure of how much a material can become magnetized in an applied magnetic field compared to vacuum. When \(\mu_r \gg 1\), it indicates that the material is highly magnetic, typically found in ferromagnetic materials. Examples of substances with \(\mu_r \gg 1\) include iron, cobalt, and nickel.

For diamagnetic substances $\chi <0$

small and negative