A material of magnetic susceptibility 499 is placed in a magnetising field of 1000 A/m. The magnetic field inside it is about (μ₀ = 4π × 10^-7 T m/A):

A6.3 × 10^-4 T
B1.3 × 10^-3 T
C
0.5 T
D
0.63 T

Q147. AI-generated practice Single-correct MCQ Medium

A small piece of a diamagnetic material placed in a non-uniform magnetic field tends to move:

A
nowhere; it experiences no force
B
from the stronger to the weaker region of the field
C
from the weaker to the stronger region
D
perpendicular to the field without preference

Q148. AI-generated practice Single-correct MCQ Medium

A superconductor below its critical temperature expels magnetic field lines from its interior. Its magnetic susceptibility is:

A
+1
B
0
C
very large and positive
D
−1

Q149. AI-generated practice Single-correct MCQ Easy

The relative permeability μ_r and magnetic susceptibility χ of a material are related by:

Aμ_r = χ
Bμ_r = 1 − χ
Cμ_r = 1/χ
Dμ_r = 1 + χ

Q150. AI-generated practice Single-correct MCQ Medium

The susceptibility of a paramagnetic salt is χ at 300 K. Assuming Curie's law, its susceptibility at 150 K is:

A
χ/2
B
χ
C
2χ
D
4χ

Q151. AI-generated practice Single-correct MCQ Hard

A material suitable for making a permanent magnet should have:

A
high retentivity and low coercivity
B
low retentivity and low coercivity
C
low retentivity and high coercivity
D
high retentivity and high coercivity

Q152. AI-generated practice Single-correct MCQ Medium

The area enclosed by the hysteresis loop (B–H curve) of a ferromagnetic material represents:

A
the energy dissipated per unit volume in one cycle of magnetisation
B
the magnetic moment of the sample
C
the retentivity of the material
D
the susceptibility of the material

Q153. AI-generated practice Single-correct MCQ Hard

A long solenoid with 1000 turns per metre carries a current of 0.5 A and has an iron core of relative permeability 800. The magnetic field inside the core is about (μ₀ = 4π × 10^-7 T m/A):

A6.3 × 10^-4 T
B
0.25 T
C
0.50 T
D
1.0 T

Q154. AI-generated practice Single-correct MCQ Medium

Diamagnetism arises in a material because:

A
its free electrons stop moving
B
its atoms have permanent magnetic moments that align with the field
C
the applied field changes the orbital motion of the electrons so as to oppose the field
D
its domains align with the applied field

Q155. AI-generated practice Numerical value Easy

The magnetic susceptibility of a material is 599. Find its relative permeability.

Q156. AI-generated practice Numerical value Medium

A magnetised rod of volume 1.5 × 10^-4 m³ has a magnetic moment of 3 A m². If its magnetisation is x × 10⁴ A/m, find x.

Q157. AI-generated practice Numerical value Medium

A paramagnetic material has susceptibility 1.2 × 10^-5 at 300 K. Assuming Curie's law, if its susceptibility at 200 K is x × 10^-6, find x.

Q158. AI-generated practice Numerical value Hard

In a magnetising field H = 2000 A/m, a material acquires a magnetisation M = 8 × 10⁵ A/m. Find its relative permeability.

Q159. AI-generated practice Assertion–Reason Medium

Assertion (A): Soft iron is used to make the core of an electromagnet.
Reason (R): Soft iron has low retentivity and low coercivity, so it is easily magnetised and demagnetised.

A
Both A and R are true and R is the correct explanation of A
B
Both A and R are true but R is not the correct explanation of A
C
A is true but R is false
D
A is false but R is true

Q160. AI-generated practice Assertion–Reason Hard

Assertion (A): The susceptibility of a diamagnetic substance is almost independent of temperature.
Reason (R): Diamagnetism arises from the alignment of permanent atomic magnetic moments along the applied field.

A
Both A and R are true and R is the correct explanation of A
B
Both A and R are true but R is not the correct explanation of A
C
A is true but R is false
D
A is false but R is true