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प्रश्न
Explain the magnetization of a material.
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उत्तर
Magnetization:
- The ratio of magnetic moment to the volume of the material is called magnetization.
- It is denoted by `vec"M"`.
- If a magnetic specimen of volume ‘V’ acquires net magnetic dipole moment ‘mnet’ due to the magnetizing field, then `vec"M" = "m"_"net"/"V"`
- It is a vector quantity.
- Unit: Am-1 in SI system.
- Dimensions: [M0 L-1 T0 I1]
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संबंधित प्रश्न
What is Magnetization?
Find the magnetization of a bar magnet of length 10 cm and cross-sectional area 4 cm2, if the magnetic moment is 2 Am2.
What is Magnetic intensity?
Give two points to distinguish between a paramagnetic and a diamagnetic substance ?
Which of the following pairs has quantities of the same dimensions?
(a) Magnetic field B and magnetising field intensity H
(b) Magnetic field B and intensity of magnetisation I
(c) Magnetising field intensity H and intensity of magnetisation I
(d) Longitudinal strain and magnetic susceptibility
Mark out the correct options.
(a) Diamagnetism occurs in all materials.
(b) Diamagnetism results from the partial alignment of permanent magnetic moment.
(c) The magnetising field intensity, H, is always zero in free space.
(d) The magnetic field of induced magnetic moment is opposite the applied field.
The magnetic field inside a long solenoid of 50 turns cm−1 is increased from 2.5 × 10−3 T to 2.5 T when an iron core of cross-sectional area 4 cm2 is inserted into it. Find (a) the current in the solenoid (b) the magnetisation I of the core and (c) the pole strength developed in the core.
The magnetic field B and the magnetic intensity H in a material are found to be 1.6 T and 1000 A m−1, respectively. Calculate the relative permeability µr and the susceptibility χ of the material.
Assume that each iron atom has a permanent magnetic moment equal to 2 Bohr magnetons (1 Bohr magneton equals 9.27 × 10−24 A m2). The density of atoms in iron is 8.52 × 1028 atoms m−3. (a) Find the maximum magnetisation I in a long cylinder of iron (b) Find the maximum magnetic field B on the axis inside the cylinder.
At a certain temperature, a ferromagnetic material becomes paramagnetic. What is this temperature called?
Answer the following question.
Define the term "Intensity" in the photon picture of electromagnetic radiation.
When a plate of magnetic material of size 10 cm × 0.5 cm × 0.2 cm (length, breath, and thickness respectively) is located in a magnetizing field of 0.5 × 104 A/m-1, then a magnetic moment of 0.5 Am2 is induced in it. Find the magnetic induction in the plate.
What does the ratio of magnetization to magnetic intensity indicate?
A solenoid has a core of material with relative permeability 500 and its windings carry a current of 1 A. The number of turns of the solenoid is 500 per meter. Calculate the magnetization of the material.
Define magnetic intensity.
An iron rod is placed parallel to magnetic field of intensity 2000 A/m. The magnetic flux through the rod is 6 × 10−4 Wb and its cross-sectional area is 3cm2. The magnetic permeability of the rod in `"Wb"/("A" - "m")` is ____________.
An electron moves in a circular orbit with uniform speed v. It produces a magnetic field B at the centre of the circle. The radius of the circle is [µ0 = permeability of free space, e = electronic charge]
A steel wire of length I has a magnetic moment M. It is then bent into a semicircular arc. The new magnetic moment is ______.
For an isotropic medium B, µ, H and M, are related as (where B, µ0, H and Mz have their usual meaning in the context of magnetic material) ____________.
The magnetization of bar magnet of length 5 cm, cross-sectional area 2 cm2 and net magnetic moment 1 Am2 is ______.
An iron rod of cross-sectional area 6 sq. cm is placed with its length parallel to a magnetic field of intensity 1200 Alm. The flux through the rod is 60 x 10-4 Wb. The permeability of the rod is ______.
The permeability of a metal is 0.01256 TmA- 1 What is its relative permeability?
Two parallel wires of equal lengths are separated by a distance of 3m from each other. The currents flowing through first and second wire is 3A and 4.5A respectively in opposite directions. The resultant magnetic field at the mid-point of both wire is (µ0 = permeability of free space).
Assertion: Susceptibility is defined as the ratio of intensity of magnetisation I to magnetic intensity H.
Reason: Greater the value of susceptibility, smaller the value of intensity of magnetisation I.
What is the magnetization of a bar magnet having length 5 cm and area of cross section 2 cm2? (M = 1 Am2)
If Mz = magnetization of a paramagnetic sample, B external magnetic field, T = absolute temperature, C = curie constant then according to Curie's law in magnetism, the correct relation is ______.
The magnetic susceptibility of paramagnetic materials is ____________.
A bar magnet having length 5 cm and area of cross-section 4cm2 has magnetic moment 2Am2. If magnetic susceptibility is 5 x 10-6, the magnetic intensity will be ____________.
A particle of charge 'q' and mass 'm' moves in a circular orbit of radius 'r' with angular speed `omega`. The ratio of the magnitude of its magnetic moment to that of its angular momentum is ____________.
The variation of intensity of magnetization (I) and applied magnetic field intensity (H) for three magnetic materials A, B, C are shown in the graph. The material A is ____________.
A bar magnet has length 3 cm, cross-sectional area 4 cm2, and magnetic moment 6 Am2. The intensity of magnetisation of bar magnet is ______.
The magnetic moment produced in a substance of mass 5 gram is 6 x 10-7 Am2 If its density is 5 g/cm3, then intensity of magnetization in `"A"/"m"` will be ____________.
Magnetic intensity is given by ______.
Magnetic lines of force due to a bar magnet do not intersect because ______.
What are the dimensions of χ, the magnetic susceptibility? Consider an H-atom. Guess an expression for χ, upto a constant by constructing a quantity of dimensions of χ, out of parameters of the atom: e, m, v, R and µ0. Here, m is the electronic mass, v is electronic velocity, R is Bohr radius. Estimate the number so obtained and compare with the value of |χ| ~ 10–5 for many solid materials.
Define magnetization.
What is magnetic susceptibility?
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 B inside the superconductor will be such that ______.
State unit and dimensions of Magnetic susceptibility.
The magnetization of a bar magnet of length 4 cm, cross-sectional area 1 cm2 and magnetic moment 2 SI units is ______.
For a medium of permeability µ, its magnetic susceptibility x is [µ 0 = permeability of vacuum]
The relation between relative permeability (`mu_r`) and magnetic susceptibility (`chi_m`) is:______.
State SI unit of Magnetization.
A solenoid having 400 turns/metre has a core of a material with relative permeability 300. If a current of 0.5 A is passed through it, then the magnetisation of the core material is nearly ______.
