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Is Coercivity and Retentivity directly proportional?

Important Questions on Magnetism and Matter

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

The magnetic susceptibility is negative for:

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

A paramagnetic material has

10^{28} atoms m^{- 3}

. Its magnetic susceptibility at temperature

350 K

2.8 \times 10^{- 4}

. Its susceptibility at

300 K

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

Magnetic materials used for making permanent magnets $(P)$ and magnets in a transformer $(T)$ have different properties of the following, which property best matches for the type of magnet required?

MEDIUM

Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

Above the curie temperature the susceptibility of a ferromagnetic substance varies

HARD

Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

Nickel

(Z = 28)

combines with a uninegative monodentate ligand to form a diamagnetic complex

{[{NiL}_{4}]}^{2 -} .

The hybridisation involved and the number of unpaired electrons present in the complex are respectively:

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

The meniscus of a liquid contained in one of the limbs of a narrow U -tube is placed between the poles of an electromagnet with the meniscus in a line with the field. The liquid is seen to rise to the line. This indicate that the liquid is ___ .

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

Which one of the following characteristics is not associated with a paramagnetic material?

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

In a ferroelectric material, as the applied field is gradually reduced to zero, the polarization still left is known as

MEDIUM

Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

Hysteresis loops for two magnetic materials

A

and

B

are given below:
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These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use:

MEDIUM

Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

The figure gives experimentally measured

B

vs.

H

variation in a ferromagnetic material. The retentivity, coercivity and saturation, respectively, of the material are:

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

The magnetic susceptibility of a paramagnetic substance at

- 173 ° C

1.5 \times 10^{- 2}

. To have the susceptibility

0.5 \times 10^{- 2}

, the change in temperature in

° C

MEDIUM

Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

Consider the regular array of vertical identical current-carrying wires (with the direction of current flow as indicated in the figure below) protruding through a horizontal table. If we scatter some diamagnetic particles on the table, they are likely to accumulate-

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

Substances, when placed in a magnetic field acquire feeble magnetisation in the direction opposite to that of the applied field are called

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Physics>Electricity and Magnetism>Magnetism and Matter>Magnetic Properties of Materials

A perfectly diamagnetic sphere has a small spherical cavity at its centre, which is filled with a paramagnetic substance. The whole system is placed in a uniform magnetic field $\vec{B}$ . Then the field inside the paramagnetic substance is:

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