03. Magnetism, Magnetic Properties and Magnetisation
Magnetism and Matter

154377 Assertion : The ferromagnetic substance do not obey Curie's law .
Reason: At Curie point a ferromagnetic substance start behaving as a paramagnetic substance.

1 If both Assertion and Reason are correct and reason is the correct explanation of Assertion.
2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
3 If Assertion is correct but Reason is incorrect
4 If both the Assertion and Reason are incorrect
Magnetism and Matter

154379 A magnet makes 40 oscillations per minute at a place having magnetic intensity of $0.1 \times 10^{-5}$ tesla. At another place it takes $2.5 \mathrm{sec}$ to complete one oscillation. The value of earth's horizontal field at that place is

1 $0.76 \times 10^{-6}$ tesla
2 $0.18 \times 10^{-6}$ tesla
3 $0.09 \times 10^{-6}$ tesla
4 $0.36 \times 10^{-6}$ tesla
Magnetism and Matter

154381 Of the following Fig., the lines of magnetic induction due to a magnet $\mathrm{SN}$, are given by

1 1
2 2
3 3
4 4
Magnetism and Matter

154389 The magnetic moment produced in a substance of $1 \mathrm{~g}$ is $6 \times 10^{-7} \mathrm{~A}-\mathrm{m}^{2}$. If its density is $5 \mathrm{~g} \mathrm{~cm}^{-3}$, then the intensity of magnetization in $\mathrm{A} / \mathrm{m}$ will be

1 3.0
2 $3 \times 10^{-6}$
3 $8.3 \times 10^{6}$
4 $1.2 \times 10^{-7}$
Magnetism and Matter

154397 A magnetic needle lying parallel to the magnetic field requires $W$ units of work to turn it through an angle $45^{\circ}$. The torque required to maintain the needle in this position will be

1 $\sqrt{2} \mathrm{~W}$
2 $\frac{1}{\sqrt{3} \mathrm{~W}}$
3 $(\sqrt{2}-1) \mathrm{W}$
4 $\frac{\mathrm{W}}{(\sqrt{2}-1)}$
Magnetism and Matter

154377 Assertion : The ferromagnetic substance do not obey Curie's law .
Reason: At Curie point a ferromagnetic substance start behaving as a paramagnetic substance.

1 If both Assertion and Reason are correct and reason is the correct explanation of Assertion.
2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
3 If Assertion is correct but Reason is incorrect
4 If both the Assertion and Reason are incorrect
Magnetism and Matter

154379 A magnet makes 40 oscillations per minute at a place having magnetic intensity of $0.1 \times 10^{-5}$ tesla. At another place it takes $2.5 \mathrm{sec}$ to complete one oscillation. The value of earth's horizontal field at that place is

1 $0.76 \times 10^{-6}$ tesla
2 $0.18 \times 10^{-6}$ tesla
3 $0.09 \times 10^{-6}$ tesla
4 $0.36 \times 10^{-6}$ tesla
Magnetism and Matter

154381 Of the following Fig., the lines of magnetic induction due to a magnet $\mathrm{SN}$, are given by

1 1
2 2
3 3
4 4
Magnetism and Matter

154389 The magnetic moment produced in a substance of $1 \mathrm{~g}$ is $6 \times 10^{-7} \mathrm{~A}-\mathrm{m}^{2}$. If its density is $5 \mathrm{~g} \mathrm{~cm}^{-3}$, then the intensity of magnetization in $\mathrm{A} / \mathrm{m}$ will be

1 3.0
2 $3 \times 10^{-6}$
3 $8.3 \times 10^{6}$
4 $1.2 \times 10^{-7}$
Magnetism and Matter

154397 A magnetic needle lying parallel to the magnetic field requires $W$ units of work to turn it through an angle $45^{\circ}$. The torque required to maintain the needle in this position will be

1 $\sqrt{2} \mathrm{~W}$
2 $\frac{1}{\sqrt{3} \mathrm{~W}}$
3 $(\sqrt{2}-1) \mathrm{W}$
4 $\frac{\mathrm{W}}{(\sqrt{2}-1)}$
Magnetism and Matter

154377 Assertion : The ferromagnetic substance do not obey Curie's law .
Reason: At Curie point a ferromagnetic substance start behaving as a paramagnetic substance.

1 If both Assertion and Reason are correct and reason is the correct explanation of Assertion.
2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
3 If Assertion is correct but Reason is incorrect
4 If both the Assertion and Reason are incorrect
Magnetism and Matter

154379 A magnet makes 40 oscillations per minute at a place having magnetic intensity of $0.1 \times 10^{-5}$ tesla. At another place it takes $2.5 \mathrm{sec}$ to complete one oscillation. The value of earth's horizontal field at that place is

1 $0.76 \times 10^{-6}$ tesla
2 $0.18 \times 10^{-6}$ tesla
3 $0.09 \times 10^{-6}$ tesla
4 $0.36 \times 10^{-6}$ tesla
Magnetism and Matter

154381 Of the following Fig., the lines of magnetic induction due to a magnet $\mathrm{SN}$, are given by

1 1
2 2
3 3
4 4
Magnetism and Matter

154389 The magnetic moment produced in a substance of $1 \mathrm{~g}$ is $6 \times 10^{-7} \mathrm{~A}-\mathrm{m}^{2}$. If its density is $5 \mathrm{~g} \mathrm{~cm}^{-3}$, then the intensity of magnetization in $\mathrm{A} / \mathrm{m}$ will be

1 3.0
2 $3 \times 10^{-6}$
3 $8.3 \times 10^{6}$
4 $1.2 \times 10^{-7}$
Magnetism and Matter

154397 A magnetic needle lying parallel to the magnetic field requires $W$ units of work to turn it through an angle $45^{\circ}$. The torque required to maintain the needle in this position will be

1 $\sqrt{2} \mathrm{~W}$
2 $\frac{1}{\sqrt{3} \mathrm{~W}}$
3 $(\sqrt{2}-1) \mathrm{W}$
4 $\frac{\mathrm{W}}{(\sqrt{2}-1)}$
Magnetism and Matter

154377 Assertion : The ferromagnetic substance do not obey Curie's law .
Reason: At Curie point a ferromagnetic substance start behaving as a paramagnetic substance.

1 If both Assertion and Reason are correct and reason is the correct explanation of Assertion.
2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
3 If Assertion is correct but Reason is incorrect
4 If both the Assertion and Reason are incorrect
Magnetism and Matter

154379 A magnet makes 40 oscillations per minute at a place having magnetic intensity of $0.1 \times 10^{-5}$ tesla. At another place it takes $2.5 \mathrm{sec}$ to complete one oscillation. The value of earth's horizontal field at that place is

1 $0.76 \times 10^{-6}$ tesla
2 $0.18 \times 10^{-6}$ tesla
3 $0.09 \times 10^{-6}$ tesla
4 $0.36 \times 10^{-6}$ tesla
Magnetism and Matter

154381 Of the following Fig., the lines of magnetic induction due to a magnet $\mathrm{SN}$, are given by

1 1
2 2
3 3
4 4
Magnetism and Matter

154389 The magnetic moment produced in a substance of $1 \mathrm{~g}$ is $6 \times 10^{-7} \mathrm{~A}-\mathrm{m}^{2}$. If its density is $5 \mathrm{~g} \mathrm{~cm}^{-3}$, then the intensity of magnetization in $\mathrm{A} / \mathrm{m}$ will be

1 3.0
2 $3 \times 10^{-6}$
3 $8.3 \times 10^{6}$
4 $1.2 \times 10^{-7}$
Magnetism and Matter

154397 A magnetic needle lying parallel to the magnetic field requires $W$ units of work to turn it through an angle $45^{\circ}$. The torque required to maintain the needle in this position will be

1 $\sqrt{2} \mathrm{~W}$
2 $\frac{1}{\sqrt{3} \mathrm{~W}}$
3 $(\sqrt{2}-1) \mathrm{W}$
4 $\frac{\mathrm{W}}{(\sqrt{2}-1)}$
Magnetism and Matter

154377 Assertion : The ferromagnetic substance do not obey Curie's law .
Reason: At Curie point a ferromagnetic substance start behaving as a paramagnetic substance.

1 If both Assertion and Reason are correct and reason is the correct explanation of Assertion.
2 If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion
3 If Assertion is correct but Reason is incorrect
4 If both the Assertion and Reason are incorrect
Magnetism and Matter

154379 A magnet makes 40 oscillations per minute at a place having magnetic intensity of $0.1 \times 10^{-5}$ tesla. At another place it takes $2.5 \mathrm{sec}$ to complete one oscillation. The value of earth's horizontal field at that place is

1 $0.76 \times 10^{-6}$ tesla
2 $0.18 \times 10^{-6}$ tesla
3 $0.09 \times 10^{-6}$ tesla
4 $0.36 \times 10^{-6}$ tesla
Magnetism and Matter

154381 Of the following Fig., the lines of magnetic induction due to a magnet $\mathrm{SN}$, are given by

1 1
2 2
3 3
4 4
Magnetism and Matter

154389 The magnetic moment produced in a substance of $1 \mathrm{~g}$ is $6 \times 10^{-7} \mathrm{~A}-\mathrm{m}^{2}$. If its density is $5 \mathrm{~g} \mathrm{~cm}^{-3}$, then the intensity of magnetization in $\mathrm{A} / \mathrm{m}$ will be

1 3.0
2 $3 \times 10^{-6}$
3 $8.3 \times 10^{6}$
4 $1.2 \times 10^{-7}$
Magnetism and Matter

154397 A magnetic needle lying parallel to the magnetic field requires $W$ units of work to turn it through an angle $45^{\circ}$. The torque required to maintain the needle in this position will be

1 $\sqrt{2} \mathrm{~W}$
2 $\frac{1}{\sqrt{3} \mathrm{~W}}$
3 $(\sqrt{2}-1) \mathrm{W}$
4 $\frac{\mathrm{W}}{(\sqrt{2}-1)}$