Download App

Magnetic Materials — Physics STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 SciencePhysicsMagnetic Materials4 Marks
Question
Permeability and Permittivity:
Magnetic Permeability is a term analogous to permittivity in electrostatics. It basically tells us about the number of magnetic lines of force that are passing through a given substance when it is kept in an external magnetic field. The number is the indicator of the behaviour of the material in magnetic field. For superconductors χ = – 1. If you substitute in the Eq. (11.18), it is observed that permeability of material µ = 0. This means no magnetic lines will pass through the superconductor.

Magnetic Susceptibility (χ) is the indicator of measure of the response of a given material to the external applied magnetic field. In other words it indicates as to how much magnetization will be produced in a given substance when kept in an external magnetic field. Again it is analogous to electrical susceptibility. This means when the substance is kept in a magnetic field, the atomic dipole moments either align or oppose the external magnetic field. If the atomic dipole moments of the substance are opposing the field, χ is observed to be negative, and if the atomic dipole moments align themselves in the direction of field, χ is observed to be positive. The number of atomic dipole moments of getting aligned in the direction of the applied magnetic field is proportional to χ. It is large for soft iron (χ >1000).

✓

Answer

Magnetic permeability is analogous to electric permittivity, both indicating the extent to which a material permits a field to pass through or permeate into the material. For a superconductor, χ = -1 which makes µ = 0, so that a superconductor does not allow magnetic field lines to pass through it.

Magnetic susceptibility (χ). analogous to electrical susceptibility, is a measure of the response of a given material to an applied magnetic field. That is, it indicates the extent of the magnetization produced in the material when it is placed in an external magnetic field. χ is positive when the atomic dipole moments align themselves in the direction of the applied field; χ is negative when the atomic dipole moments align antiparallel to the field. χ is large for soft iron (χ > 1000).

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Answer the following in Detail" from Magnetic Materials→Magnetic Materials — all question types→Physics STD 12 Science question papers→Maharashtra Board STD 12 Science question papers→Maharashtra Board question paper generator→

Similar questions

What about the kinetic friction between the road and the lyres?
→
In an adiabatic process, the pressure of the gas drops from $1 \times 10^5 N / m ^2$ to $5 \times 10^4 N / m ^2$ and the temperature drops from $27^{\circ} C$ to $-46^{\circ} C$. Find the adiabatic ratio for the gas.
→
A carnival event known as a "well of death" consists of a large vertical cylinder inside which usually a stunt motorcyclist rides in horizontal circles. Show that the minimum speed necessary to keep the rider from falling is given by $\mathrm{v}=\sqrt{\mathrm{rg} / \mu_s}$, in usual notations.
→
A $dc$ ammeter and an $ac$ hot $-$ wire ammeter are connected to a circuit in series. When a direct current is passed through the circuit, the $dc$ ammeter shows $6 A$. When a pure alternating current is passed, the $ac$ ammeter shows $8 A$. What will be the reading of each ammeter if the direct and alternating currents pass simultaneously through the circuit?
→
Explain the construction and propagation of a plane wavefront using Huygens’ principle.
→
Monochromatic electromagnetic radiation from a distant source passes through a slit. The diffraction pattern is observed on a screen 2.50 m from the slit. If the width of the central maximum is 6.00 mm, what is the slit width if the wavelength is
(a) 500 nm (visible light);
(b) 50 µm (infrared radiation);
(c) 0.500 nm (X-rays)?

→
Show that in an $AC$ circuit containing a pure inductor, the voltage is ahead of current by $\pi/2$ in phase.
→
Explain the concept/phenomenon of mutual induction.###Explain and define mutual inductance of a coil with respect to another coil.###Define the coefficient of mutual induction.
→
Obtain the relation between surface energy and surface tension.
Calculate the work done in blowing a soap bubble to a radius of $1 \ cm$. The surface tension of a soap solution is $2.5 \times 10^{-2} \ N / m$.
→
Derive an expression for the work done during an isothermal process
$104 J$ of work is done on certain volume of a gas. If the gas releases $125 \ kJ$ of heat, calculate the change in internal energy of the gas.
→