Alpha Question Bank for Medical: Physics>Chapter 26 - Matter and Magnetism>Exercise-2>Q 12

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The coercivity of a small magnet where the ferromagnet gets demagnetized is $3 \times 10^{3} A m^{- 1} .$ The current required to be passed in a solenoid of length $20 cm$ and number of turns $100,$ so that the magnetic gets demagnetized when inside the solenoid, is___

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Important Questions on Matter and Magnetism

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Alpha Question Bank for Medical: Physics>Chapter 26 - Matter and Magnetism>Exercise-2>Q 13

Hysteresis loops for two magnetic materials $A$ and $B$ are given below:

(A) Question Image (B)

These materials are used to make magnets for electric generators, transformer cores and electromagnet cores. Then it is proper to use

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Alpha Question Bank for Medical: Physics>Chapter 26 - Matter and Magnetism>Exercise-2>Q 14

A bar magnet is demagnetized by inserting it inside a solenoid of length

0.2

m

,

100

turns, and carrying a current of

5.2

A

. The coercivity of the bar magnet is:

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Alpha Question Bank for Medical: Physics>Chapter 26 - Matter and Magnetism>Exercise-2>Q 15

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:

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Alpha Question Bank for Medical: Physics>Chapter 26 - Matter and Magnetism>Exercise-2>Q 16

A paramagnetic substance, in the form of a cube with sides

11 cm

, has a magnetic dipole moment of

20 \times 10^{- 6} J T^{- 1}

, when a magnetic intensity of

60 \times 10^{3} A m^{- 1}

is applied. Its magnetic susceptibility is

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Alpha Question Bank for Medical: Physics>Chapter 26 - Matter and Magnetism>Exercise-2>Q 17

A paramagnetic material has

10^{28} atoms m^{- 3}

. Its magnetic susceptibility at temperature

350 K

is

2.8 \times 10^{- 4}

. Its susceptibility at

300 K

is

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Alpha Question Bank for Medical: Physics>Chapter 26 - Matter and Magnetism>Exercise-3>Q 1

A rectangular coil of

100

turns has length

4 cm

and width

5 cm .

It is placed with its plane parallel to a uniform magnetic field and a current of

2 A

is sent through the coil. Find the magnitude of the magnetic field

B,

if the torque acting on the coll is

0.2 N - m .

.