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How susceptibility of a ferromagnetic material varies with temperature?

Important Questions on Matter and Magnetism

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The magnetization of bar magnet of length 5 cm, cross-sectional area 2 cm2 and net magnetic moment 1 A m2 is
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Which one of the following characteristics is not associated with a paramagnetic material?
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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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Coercivity of a magnet where the ferromagnet gets completely demagnetized is 3×103Am-1. The minimum current required to be passed in a solenoid having 1000 turns per metre, so that the magnet gets completely demagnetized when placed inside the solenoid is
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A domain in ferromagnetic iron in the form of cube is having 5×105 atoms. If the side length of this domain is 1.5 μm and each atom has a dipole moment of 8×10-24 A m2, then magnetisation of domain is 
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An iron rod of susceptibility 599 is subjected to a magnetising field of 1200 A m1. The permeability of the material of the rod is:
μ0=4π×107 T m A1
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An example of a perfect diamagnet is a superconductor. This implies that when a superconductor is put in a magnetic field of intensity B, the magnetic field Bs inside the superconductor will be such that
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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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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?

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A 25 cm long solenoid has the radius 2 cm and 500 turns. It carries a current of 15 A. If it is equivalent to a magnet of the same size and magnetization M Magnetic momentvolume,then  M is:
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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 B. Then the field inside the paramagnetic substance is:

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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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A paramagnetic sample shows a net magnetisation of 6 A m-1 when it is placed in an external magnetic field of 0.4 T at a temperature of 4 K. When the sample is placed in an external magnetic field of 0.3 T at a temperature of 24 K, then the magnetisation will be :
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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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A paramagnetic sample shows a net magnetization of 8 Am-1 when placed in an external magnetic field of 0.6 T at a temperature of 4 K. When the same sample is placed in an external magnetic field of 0.2 T at a temperature of 16 K. The magnetization will be
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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:
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The coercivity of a small magnet, where the ferromagnet gets demagnetised is 3×103 A/m. The current required to be passed in a solenoid of length 10 cm and number of turns 100, so that the magnet gets demagnetised when inside the solenoid is
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A paramagnetic material has 1028 atoms m-3. Its magnetic susceptibility at temperature 350 K is 2.8×10-4. Its susceptibility at 300 K is