MEDIUM

Earn 100

What is the name of the alternative therapy that uses magnets to improve health?

50% studentsanswered this correctly

Important Questions on Magnetism and Matter

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

The magnetic susceptibility of a material of a rod is

499 .

Permeability in vacuum is

4 π \times 10^{- 7} {Hm}^{- 1} .

Absolute permeability of the material of the rod is

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

The relative permeability is represented by

μ_{r}

and the susceptibility is denoted by

χ

for a magnetic substance. Then, for a paramagnetic substance

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

μ_{0}

is permeability of vacuum,

χ_{m}

is susceptibility then permeability of material is

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

25 cm

long solenoid has the radius

2 cm

and

500

turns. It carries a current of

15 A

. If it is equivalent to a magnet of the same size and magnetization

\vec{M} (\frac{M a g n e t i c m o m e n t}{v o l u m e}),

then

|\vec{M}|

is:

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

A paramagnetic sample shows a net magnetisation of

6 A m^{- 1}

when it is placed in an external magnetic field of

0.4 T

at a temperature of

4 K

. When the sample is placed in an external magnetic field of

0.3 T

at a temperature of

24 K

, then the magnetisation will be :

MEDIUM

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

Following plots show Magnetization $(M)$ vs Magnetising field $(H)$ and Magnetic susceptibility $(χ)$ vs Temperature $(T)$ graph :

Question Image

Which of the following combination will be represented by a diamagnetic material?

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

A solenoid has core of a material with relative permeability

501

and its windings carry a current of

1 A .

The number of turns of the solenoid is

500 m^{- 1}

. The magnetisation of the material is

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

Electromagnets are made of soft iron because, soft iron has

MEDIUM

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

An iron rod of susceptibility

599

is subjected to a magnetising field of

1200 A m^{- 1}

. The permeability of the material of the rod is:

(μ_{0} = 4 π \times 10^{- 7} T m A^{- 1})

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

Magnetization of the sample is

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

The unit of magnetic flux density is

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

The magnetization of bar magnet of length

5 cm

, cross-sectional area

2 {cm}^{2}

and net magnetic moment

1 A m^{2}

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

Magnetic susceptibility for a paramagnetic and diamagnetic material is respectively

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

The property of the substance which shows how easily a substance can be magnetized, when placed in a magnetic field is called

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

In a permanent magnet at room temperature

HARD

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

A hoop and a solid cylinder of same mass and radius are made of a permanent magnetic material with their respective axes. But the magnetic moment of hoop is twice of solid cylinder. They are placed in a uniform magnetic field in such a manner that their magnetic moments make a small angle with the field. If the oscillation periods of hoop and cylinder are

T_{h}

and

T_{c}

respectively, then:

HARD

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

At some location the horizontal component of earth's magnetic field is

18 \times 10^{- 6} T .

At this location, magnetic needle of length

0.12 m

and pole strength

1.8 Am

is suspended from its mid-point using a thread, it makes

45 °

angles with horizontal in equilibrium. To keep this needle horizontal, the vertical force that should be applied at one of its ends is:

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

Susceptibility of a diamagnetic substance is

EASY

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

Magnetic susceptibility of a paramagnetic substance is

MEDIUM

Physics>Electricity and Magnetism>Magnetism and Matter>Permanent Magnets and Electromagnets

A domain in ferromagnetic iron in the form of cube is having

5 \times 10^{5}

atoms. If the side length of this domain is

1.5 μm

and each atom has a dipole moment of

8 \times 10^{- 24} A m^{2}

, then magnetisation of domain is

What is the name of the alternative therapy that uses magnets to improve health?

Important Questions on Magnetism and Matter

Learn and Prepare for any exam you want !