Diamagnetism, Paramagnetism & Ferromagnetism — MH-CET Physics MCQs with Solutions
Free MH-CET Physics Diamagnetism, Paramagnetism & Ferromagnetism MCQs with step-by-step solutions (21 questions). Part of Magnetic Materials. Practise online on Prepizo — no login needed.
▶ Practise Diamagnetism, Paramagnetism & Ferromagnetism online (free)
Questions with solutions
Q1 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · theory
The magnetic susceptibility of a diamagnetic substance is:
A. Small, positive and inversely proportional to temperature
B. Zero at all temperatures
C. Large and positive
D. Small, negative and independent of temperature ✓ Correct
Solution: Diamagnetism arises from induced orbital currents that oppose the applied field, a mechanism unaffected by thermal agitation.
Q2 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · theory
The magnetic susceptibility of a paramagnetic substance is:
A. Large and positive
B. Large and negative
C. Small and negative
D. Small and positive ✓ Correct
Solution: Permanent atomic dipoles align partially with the applied field, giving a weak positive magnetisation.
Q3 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · theory
The magnetic susceptibility of a ferromagnetic substance is:
A. Very large and positive ✓ Correct
B. Small and positive
C. Zero
D. Very large and negative
Solution: Domain alignment produces magnetisation thousands of times greater than the applied magnetising field.
Q4 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · theory
A diamagnetic substance placed in a non-uniform magnetic field tends to move:
A. Not at all
B. Perpendicular to the field
C. From the weaker to the stronger part of the field
D. From the stronger to the weaker part of the field ✓ Correct
Solution: Its induced moment opposes the field, so it is feebly repelled and seeks the region of least field.
Q5 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · theory
A paramagnetic substance placed in a non-uniform magnetic field is:
A. Strongly attracted and retains magnetism
B. Strongly repelled
C. Feebly attracted towards the stronger part of the field ✓ Correct
D. Unaffected
Solution: Its dipoles align with the field, giving a weak attraction that disappears when the field is removed.
Q6 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · theory
A ferromagnetic substance differs from a paramagnetic one chiefly in that it:
A. Is strongly attracted and retains magnetism after the field is removed ✓ Correct
B. Has a negative susceptibility
C. Is feebly repelled by a magnet
D. Cannot be magnetised at all
Solution: Ferromagnetic domains remain partly aligned after the field is withdrawn, which is what makes permanent magnets possible.
Q7 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · theory
Bismuth, copper and water are examples of:
A. Superconductors
B. Diamagnetic substances ✓ Correct
C. Ferromagnetic substances
D. Paramagnetic substances
Solution: These have no net atomic magnetic moment, so only the induced opposing effect appears.
Q8 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · theory
Domains are a characteristic feature of:
A. Diamagnetic materials
B. Ferromagnetic materials ✓ Correct
C. All materials equally
D. Paramagnetic materials
Solution: A domain is a region in which atomic moments are spontaneously aligned; an applied field grows the favourably oriented domains.
Q9 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · numerical
A material has a magnetic susceptibility of $-10^{-5}$. It is:
A. Non-magnetic
B. Paramagnetic
C. Diamagnetic ✓ Correct
D. Ferromagnetic
Solution: A small negative susceptibility is the signature of diamagnetism.
Q10 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · numerical
A material has a magnetic susceptibility of $+10^{-3}$. It is:
A. Paramagnetic ✓ Correct
B. Diamagnetic
C. Superconducting
D. Ferromagnetic
Solution: A small positive susceptibility indicates paramagnetism.
Q11 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · numerical
A material has a magnetic susceptibility of $1000$. It is:
A. Non-magnetic
B. Diamagnetic
C. Paramagnetic
D. Ferromagnetic ✓ Correct
Solution: Only ferromagnetic materials show susceptibilities of this order.
Q12 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · numerical
A material has relative permeability slightly less than $1$. It is:
A. Diamagnetic ✓ Correct
B. Ferromagnetic
C. Impossible
D. Paramagnetic
Solution: $\mu_r = 1 + \chi < 1$ requires a negative susceptibility, so the material is diamagnetic.
Q13 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · numerical
A material has relative permeability slightly greater than $1$. It is:
A. Ferromagnetic
B. Non-magnetic
C. Paramagnetic ✓ Correct
D. Diamagnetic
Solution: A small positive $\chi$ gives $\mu_r$ just above unity.
Q14 — Diamagnetism, Paramagnetism & Ferromagnetism · easy · numerical
A material has relative permeability of the order of $10^3$. It is:
A. Paramagnetic
B. Ferromagnetic ✓ Correct
C. Diamagnetic
D. A vacuum
Solution: Such a large $\mu_r$ is characteristic of ferromagnetic materials like soft iron.
Q15 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · numerical
A diamagnetic material has susceptibility $-2 \times 10^{-5}$. Its relative permeability is:
A. $0.99995$
B. $0.99998$ ✓ Correct
C. $2 \times 10^{-5}$
D. $1.00002$
Solution: $\mu_r = 1 - 2 \times 10^{-5} = 0.99998$.
Q16 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · numerical
A paramagnetic material has susceptibility $2 \times 10^{-3}$. Its relative permeability is:
A. $2 \times 10^{-3}$
B. $0.998$
C. $1.02$
D. $1.002$ ✓ Correct
Solution: $\mu_r = 1 + 2 \times 10^{-3} = 1.002$.
Q17 — Diamagnetism, Paramagnetism & Ferromagnetism · hard · numerical
A ferromagnetic material of relative permeability $5000$ is placed in a magnetising field of $100\text{ A}/\text{m}$. The induction in it is approximately:
A. $0.63\text{ T}$ ✓ Correct
B. $1.26\text{ T}$
C. $6.3\text{ T}$
D. $0.063\text{ T}$
Solution: $B = \mu_r\mu_0H = 5000 \times 1.26 \times 10^{-6} \times 100 \approx 0.63\text{ T}$.
Q18 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · numerical
For a paramagnetic material at constant applied field, the magnetisation is:
A. Inversely proportional to the absolute temperature ✓ Correct
B. Independent of the temperature
C. Proportional to the square of the temperature
D. Directly proportional to the absolute temperature
Solution: By Curie's law the alignment achieved against thermal agitation falls as $\dfrac{1}{T}$.
Q19 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · numerical
The susceptibilities of a paramagnetic sample at $300\text{ K}$ and $600\text{ K}$ are in the ratio:
A. $1 : 2$
B. $4 : 1$
C. $2 : 1$ ✓ Correct
D. $1 : 1$
Solution: Curie's law gives $\chi \propto \dfrac{1}{T}$, so $\dfrac{\chi_1}{\chi_2} = \dfrac{600}{300} = 2$.
Q20 — Diamagnetism, Paramagnetism & Ferromagnetism · medium · numerical
When the temperature of a diamagnetic material is raised, its susceptibility:
A. Decreases sharply
B. Remains practically unchanged ✓ Correct
C. Increases sharply
D. Becomes positive
Solution: Diamagnetism arises from induced orbital motion rather than the alignment of permanent dipoles, so it is essentially temperature independent.
Q21 — Diamagnetism, Paramagnetism & Ferromagnetism · hard · numerical
A superconductor below its critical temperature expels magnetic flux completely. Its magnetic susceptibility is:
A. $-1$ ✓ Correct
B. Infinite
C. $+1$
D. $0$
Solution: Complete flux exclusion (the Meissner effect) means $M = -H$, so $\chi = -1$ — a perfect diamagnet.