03. Magnetism, Magnetic Properties and Magnetisation
Magnetism and Matter

154295 A domain in a ferromagnetic substance is in the form of a cube of length $1 \mu \mathrm{m}$. If it contains $8 \times$ $10^{10}$ atoms and each atomic dipole has a dipole moment of $9 \times 10^{-24} \mathrm{Am}^{2}$, then the magnetisation of the domain is

1 $7.2 \times 10^{5} \mathrm{Am}^{-1}$
2 $7.2 \times 10^{3} \mathrm{Am}^{-1}$
3 $7.2 \times 10^{9} \mathrm{Am}^{-1}$
4 $7.2 \times 10^{12} \mathrm{Am}^{-1}$
Magnetism and Matter

154298 A bar magnet of magnetic moment $5 \mathrm{Am}^{2}$ is placed in a uniform magnetic induction $3 \times 10^{-5}$ T. If each pole of a magnet experiences a force of $2.5 \times 10^{-4} \mathrm{~N}$ then the magnetic length of the magnet is

1 $0.2 \mathrm{~m}$
2 $0.8 \mathrm{~m}$
3 $0.6 \mathrm{~m}$
4 $0.4 \mathrm{~m}$
Magnetism and Matter

154300 The relation between total magnetic field (B), magnetic intensity $(\mathrm{H})$, permeability of free space $\left(\mu_{0}\right)$ and susceptibility $(\chi)$ is

1 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1-\chi)$
2 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1+\chi)$
3 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1+\chi)$
4 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1-\chi)$
Magnetism and Matter

154302 The susceptibility of tungsten is $6.8 \times 10^{-5}$ at temperature $300 \mathrm{~K}$. The susceptibility at temperature $400 \mathrm{~K}$ is

1 $4.8 \times 10^{-5}$
2 $6.8 \times 10^{-5}$
3 $3.4 \times 10^{-5}$
4 $5.1 \times 10^{-5}$
Magnetism and Matter

154295 A domain in a ferromagnetic substance is in the form of a cube of length $1 \mu \mathrm{m}$. If it contains $8 \times$ $10^{10}$ atoms and each atomic dipole has a dipole moment of $9 \times 10^{-24} \mathrm{Am}^{2}$, then the magnetisation of the domain is

1 $7.2 \times 10^{5} \mathrm{Am}^{-1}$
2 $7.2 \times 10^{3} \mathrm{Am}^{-1}$
3 $7.2 \times 10^{9} \mathrm{Am}^{-1}$
4 $7.2 \times 10^{12} \mathrm{Am}^{-1}$
Magnetism and Matter

154298 A bar magnet of magnetic moment $5 \mathrm{Am}^{2}$ is placed in a uniform magnetic induction $3 \times 10^{-5}$ T. If each pole of a magnet experiences a force of $2.5 \times 10^{-4} \mathrm{~N}$ then the magnetic length of the magnet is

1 $0.2 \mathrm{~m}$
2 $0.8 \mathrm{~m}$
3 $0.6 \mathrm{~m}$
4 $0.4 \mathrm{~m}$
Magnetism and Matter

154300 The relation between total magnetic field (B), magnetic intensity $(\mathrm{H})$, permeability of free space $\left(\mu_{0}\right)$ and susceptibility $(\chi)$ is

1 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1-\chi)$
2 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1+\chi)$
3 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1+\chi)$
4 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1-\chi)$
Magnetism and Matter

154302 The susceptibility of tungsten is $6.8 \times 10^{-5}$ at temperature $300 \mathrm{~K}$. The susceptibility at temperature $400 \mathrm{~K}$ is

1 $4.8 \times 10^{-5}$
2 $6.8 \times 10^{-5}$
3 $3.4 \times 10^{-5}$
4 $5.1 \times 10^{-5}$
Magnetism and Matter

154295 A domain in a ferromagnetic substance is in the form of a cube of length $1 \mu \mathrm{m}$. If it contains $8 \times$ $10^{10}$ atoms and each atomic dipole has a dipole moment of $9 \times 10^{-24} \mathrm{Am}^{2}$, then the magnetisation of the domain is

1 $7.2 \times 10^{5} \mathrm{Am}^{-1}$
2 $7.2 \times 10^{3} \mathrm{Am}^{-1}$
3 $7.2 \times 10^{9} \mathrm{Am}^{-1}$
4 $7.2 \times 10^{12} \mathrm{Am}^{-1}$
Magnetism and Matter

154298 A bar magnet of magnetic moment $5 \mathrm{Am}^{2}$ is placed in a uniform magnetic induction $3 \times 10^{-5}$ T. If each pole of a magnet experiences a force of $2.5 \times 10^{-4} \mathrm{~N}$ then the magnetic length of the magnet is

1 $0.2 \mathrm{~m}$
2 $0.8 \mathrm{~m}$
3 $0.6 \mathrm{~m}$
4 $0.4 \mathrm{~m}$
Magnetism and Matter

154300 The relation between total magnetic field (B), magnetic intensity $(\mathrm{H})$, permeability of free space $\left(\mu_{0}\right)$ and susceptibility $(\chi)$ is

1 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1-\chi)$
2 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1+\chi)$
3 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1+\chi)$
4 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1-\chi)$
Magnetism and Matter

154302 The susceptibility of tungsten is $6.8 \times 10^{-5}$ at temperature $300 \mathrm{~K}$. The susceptibility at temperature $400 \mathrm{~K}$ is

1 $4.8 \times 10^{-5}$
2 $6.8 \times 10^{-5}$
3 $3.4 \times 10^{-5}$
4 $5.1 \times 10^{-5}$
Magnetism and Matter

154295 A domain in a ferromagnetic substance is in the form of a cube of length $1 \mu \mathrm{m}$. If it contains $8 \times$ $10^{10}$ atoms and each atomic dipole has a dipole moment of $9 \times 10^{-24} \mathrm{Am}^{2}$, then the magnetisation of the domain is

1 $7.2 \times 10^{5} \mathrm{Am}^{-1}$
2 $7.2 \times 10^{3} \mathrm{Am}^{-1}$
3 $7.2 \times 10^{9} \mathrm{Am}^{-1}$
4 $7.2 \times 10^{12} \mathrm{Am}^{-1}$
Magnetism and Matter

154298 A bar magnet of magnetic moment $5 \mathrm{Am}^{2}$ is placed in a uniform magnetic induction $3 \times 10^{-5}$ T. If each pole of a magnet experiences a force of $2.5 \times 10^{-4} \mathrm{~N}$ then the magnetic length of the magnet is

1 $0.2 \mathrm{~m}$
2 $0.8 \mathrm{~m}$
3 $0.6 \mathrm{~m}$
4 $0.4 \mathrm{~m}$
Magnetism and Matter

154300 The relation between total magnetic field (B), magnetic intensity $(\mathrm{H})$, permeability of free space $\left(\mu_{0}\right)$ and susceptibility $(\chi)$ is

1 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1-\chi)$
2 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1+\chi)$
3 $\frac{\mathrm{H}}{\mathrm{B}}=\mu_{0}(1+\chi)$
4 $\frac{\mathrm{B}}{\mathrm{H}}=\mu_{0}(1-\chi)$
Magnetism and Matter

154302 The susceptibility of tungsten is $6.8 \times 10^{-5}$ at temperature $300 \mathrm{~K}$. The susceptibility at temperature $400 \mathrm{~K}$ is

1 $4.8 \times 10^{-5}$
2 $6.8 \times 10^{-5}$
3 $3.4 \times 10^{-5}$
4 $5.1 \times 10^{-5}$