Magnetism and Matter

The periodic time of a magnet in vibration magnetometer is $T_0$. If a magnet is replaced by another magnet whose moment of inertia is three times and magnetic moment is one-third of the original magnet, then time period of new magnet will ...

The frequency of oscillation of a small magnet in a magnetic field of induction 'B' is '$n$'. If the frequency of oscillations of the same magnet in a field of induction 'X' falls to $\left(\dfrac{n}{3}\right)$, the value of 'X' is

A diamagnetic liquid is filled in a U-tube. One arm of a U-tube is placed in an external magnetic field with the meniscus in line with the field. The level of the liquid in that arm will

The region inside a current carrying toroid is filled with a material (Niobium) having susceptibility $\chi = 2.6 \times 10^{-5}$. The percentage increase in the magnetic field in the presence of Niobium over that without it, is

The magnetic moment produced in a sample of 2 gram is $8 \times 10^{-7}\,\text{A/m}^2$. If its density is $4\ \text{g/cm}^3$ then the magnetization of the sample is

The product of magnetic susceptibility ($\chi$) and absolute temperature (T) is constant for a

An iron rod is placed parallel to magnetic field intensity 1000 A/m. The magnetic flux through the rod is $3 \times 10^{-4}$ Wb and its cross-sectional area is $1.5\ \text{cm}^2$. The magnetic permeability of rod in $\text{Wb/}_{\text{A-m}}...

An iron rod is placed parallel to magnetic field intensity 2000 A/m. The magnetic flux through rod is $6 \times 10^{-4}$ wb and its cross sectional area is 3 cm$^2$. The magnetic permeability of the rod in wb/A-m is

A rod with a circular cross-section area $2$ cm$^2$ and length $40$ cm is wound uniformly with $400$ turns of an insulated wire. If a current $0.4$ A flows in the wire winding, the total magnetic flux produced inside the winding is $4\pi \t...

Which of the following figure best represents the variation of magnetic susceptibility ($\chi$) with temperature for a diamagnetic substance?

The magnetic field (B) inside a long solenoid having ' $n$ ' turns per unit length and carrying current ' i ' when iron core is kept in it, is ( $\mu_0=$ permeability of vacuum, $\chi=$ magnetic susceptibility)

The work done in turning a magnet of magnetic moment ' $M$ ' by an angle of $90^{\circ}$ from the meridian is ' $n$ ' times the corresponding Work done to turn it through an angle of $60^{\circ}$ where the value of ' $n$ ' is $\left(\cos 90...

A bar of iron having magnetic moment $2.4 \mathrm{Am}^2$ weighs 66 g . If the density of the material of the bar is $7700 \mathrm{~kg} / \mathrm{m}^3$, the intensity of magnetisation in $\mathrm{Am}^{-1}$ is

To protect the instrument from magnetic field, it is completely surrounded by

Susceptibility of a paramagnetic substance is

Magnetic hysteresis is exhibited by magnetic materials which are

The variation of magnetic susceptibility $(\chi)$ with temperature for a diamagnetic substance is shown correctly by graph

The space within the current carrying toroid is filled with aluminium of susceptibility ' $\chi$ '. The percentage increase in the magnetic field ' $B$ ' will be

The magnetic susceptibility of iron is 5499 . The relative permeability of iron will be

Two bar magnets A and B are geometrically similar but the magnetic moment of $A$ is twice that of $B$. $T_1$ is the time period of oscillation when their like poles are kept together. When unlike poles are kept together, the time period of ...

If $M$ is the magnetisation induced in the material, H is the magnetic field intensity, B is the net magnetic field inside the material then the correct relation between them is ( $\mu_0=$ permeability of free space)

 The correct relation between total magnetic field $(B)$, magnetic intensity $(\mathrm{H})$, permeability of free space $\left(\mu_0\right)$ and susceptibility $(\chi)$ is

The magnetic moments associated with two closely wound circular coils A and B of radius $r_A=10 \mathrm{~cm}$ and $r_B=20 \mathrm{~cm}$ respectively are equal if $\left(N_A, I_A\right.$ and $N_B, I_B$ are number of turns and current of A an...

A magnetic intensity of $500 \mathrm{~A} / \mathrm{m}$, produces a magnetic flux of $2.4 \times 10^{-5} \mathrm{~Wb}$ in an iron bar of cross-sectional area $0.4 \mathrm{~cm}^2$. The magnetic permeability of the iron bar is

The relation between total magnetic field (B), magnetic intensity $(\mathrm{H})$, permeability of free space $\left(\mu_0\right)$ and susceptibility $(\chi)$ is

A magnetic needle of magnetic moment $6 \times 10^{-2} \mathrm{Am}^2$ and moment of inertia $9.6 \times 10^{-5} \mathrm{~kg} \mathrm{~m}^2$ performs simple harmonic motion in a magnetic field of 0.01 T . Time taken to complete 10 oscillatio...

The magnetic susceptibility of the material of a rod is 599. The absolute permeability of the material of the rod will be [ $\mu_0=4 \pi \times 10^{-7}$ SI unit]

At certain place a magnet makes 30 oscillations per minute. At another place if the magnetic induction is increased by two times the magnetic induction at first place, then the time period of same magnet will be

A ferromagnetic material is heated above its curie temperature. The correct statement from the following is that

The materials having negative magnetic susceptibility are

A solenoid having 400 turns per metre has a core of a material with relative permeability 400. When a current of 0.5 A is passed through it, the magnetization of the core material in $\mathrm{Am}^{-1}$ is nearly

A bar magnet has length 4 cm , cross-sectional area $2 \mathrm{~cm}^2$ and magnetic moment $6 \mathrm{Am}^2$. The intensity of magnetisation of bar magnet is

In the following graph of flux density versus magnetizing force, coercivity and retentivity are respectively represented by the points

The materials suitable for making electromagnets should have

A thin rod of length \(L\) has magnetic moment \(M\) when magnetised. If rod is bent in a semicircular arc what is magnetic moment in new shape?

In the hysteresis curve the value of magnetization (B) which will be present in a substance when value of magnetizing force \((\mathrm{H})\) is made zero \((\mathrm{H}=0)\) is called as

For which of the following substances, the magnetic susceptibility is independent of temperature?

Magnetic shielding is done by surrounding the instrument to be protected from magnetic field by

According to Curie's law in magnetism, the correct relation is ( \(\mathrm{M}=\) magnetization in paramagnetic sample, \(\mathrm{B}=\) applied magnetic field, \(\mathrm{T}=\) absolute temperature of the material, \(\mathrm{C}=\) curie's con...

A solenoid of 500 turns/m is carrying a current of 3 A. Its core is made of iron which has relative permeability 5001. The magnitude of magnetization is

The magnetic susceptibility of the material of a rod is 349 and permeability of vacuum \(\mu_0\) is \(4 \pi \times 10^{-7}\) SI units. Absolute permeability of the material of the rod in SI units is

A current '\(I\)' is flowing in a conductor of length '\(L\)' when it is bent in the form of a circular loop, its magnetic moment will be

A magnetic dipole of magnetic moment \(\mathrm{M}\), is freely suspended in a magnetic field of induction B. The minimum and maximum values of potential energy of the dipole, respectively are

Two bar magnets '\(\mathrm{P}\)' and '\(\mathrm{Q}\)' are kept in uniform magnetic field '\(\mathrm{B}\)' with magnetic moments '\(\mathrm{M_P}\)' and '\(\mathrm{M_Q}\)' respectively. Magnet 'P' is oscillating with frequency twice that of m...

A bar magnet has length \(3 \mathrm{~cm}\), cross-sectional area \(2 \mathrm{~cm}^2\) and magnetic moment \(3 \mathrm{~Am}^2\). The intensity of magnetisation of bar magnet is

The permeability of a metal is \(0.1256 ~\mathrm{TmA}^{-1}\). Its relative permeability will be \(\mathrm{\left( {{{{\mu _0}} \over {4\pi }} = {{10}^{ - 7}}\,SI\,unit} \right)}\) (\(\pi=3.14\))

The relative permeability of iron is 2000. Its absolute permeability in SI unit will be \(\left(\frac{\mu_0}{4 \pi}=10^{-7} \text{SI unit}\right)\)

What is susceptibility of a medium, if its relative permeability is 0.85?

The north pole of a long horizontal bar magnet is being brought towards closed circuit consisting of a coil. The direction of induced current produced in it is

For a paramagnetic substance, the magnetic susceptibility is