360517
The figure illustrates how \(B\) the flux density, inside a sample of ferromagnetic material varies with external magnetic field \(B_{o}\). For the sample to be suitable for making a permanent magnet
1 \(OQ\) should be large, \(OR\) should be small
2 \(OQ\) and \(OR\) both should be large
3 \(OQ\) should be small and \(OR\) should be large
4 \(OQ\) and \(OR\) both should be small
Explanation:
For making permanent magnet the retentivity \(OQ\) and coercive force \(OR\) must be large.
PHXII05:MAGNETISM and MATTER
360518
Core of electromagnet is made of ferromagnetic material which has
1 High retentivity
2 Low permeability
3 High permeability and low retentivity
4 None of the above
Explanation:
Conceptual Question
PHXII05:MAGNETISM and MATTER
360519
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
1 \(520\;A/m\)
2 \(1200\;A/m\)
3 \(2600\;A/m\)
4 \(285\;A/m\)
Explanation:
Coercivity of a bar magnet \(H = \frac{B}{{{\mu _0}}} = nI = \frac{N}{l}I\) \( = \frac{{100}}{{0.2}} \times 5.2 = 2600\;A/m\)
JEE - 2019
PHXII05:MAGNETISM and MATTER
360520
Hysteresis loops for two magnetic materials \(A\) and \(B\) are given below: These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use :
1 \(A\) for electromagnets and \(B\) for electric generators
2 \(A\) for transformers and \(B\) for electric generators
3 \(B\) for electromagnets and transformers
4 \(A\) for electric generators and transformers
Explanation:
For electromagnet and transformer, the coercivity should be low to reduce energy loss.
360517
The figure illustrates how \(B\) the flux density, inside a sample of ferromagnetic material varies with external magnetic field \(B_{o}\). For the sample to be suitable for making a permanent magnet
1 \(OQ\) should be large, \(OR\) should be small
2 \(OQ\) and \(OR\) both should be large
3 \(OQ\) should be small and \(OR\) should be large
4 \(OQ\) and \(OR\) both should be small
Explanation:
For making permanent magnet the retentivity \(OQ\) and coercive force \(OR\) must be large.
PHXII05:MAGNETISM and MATTER
360518
Core of electromagnet is made of ferromagnetic material which has
1 High retentivity
2 Low permeability
3 High permeability and low retentivity
4 None of the above
Explanation:
Conceptual Question
PHXII05:MAGNETISM and MATTER
360519
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
1 \(520\;A/m\)
2 \(1200\;A/m\)
3 \(2600\;A/m\)
4 \(285\;A/m\)
Explanation:
Coercivity of a bar magnet \(H = \frac{B}{{{\mu _0}}} = nI = \frac{N}{l}I\) \( = \frac{{100}}{{0.2}} \times 5.2 = 2600\;A/m\)
JEE - 2019
PHXII05:MAGNETISM and MATTER
360520
Hysteresis loops for two magnetic materials \(A\) and \(B\) are given below: These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use :
1 \(A\) for electromagnets and \(B\) for electric generators
2 \(A\) for transformers and \(B\) for electric generators
3 \(B\) for electromagnets and transformers
4 \(A\) for electric generators and transformers
Explanation:
For electromagnet and transformer, the coercivity should be low to reduce energy loss.
360517
The figure illustrates how \(B\) the flux density, inside a sample of ferromagnetic material varies with external magnetic field \(B_{o}\). For the sample to be suitable for making a permanent magnet
1 \(OQ\) should be large, \(OR\) should be small
2 \(OQ\) and \(OR\) both should be large
3 \(OQ\) should be small and \(OR\) should be large
4 \(OQ\) and \(OR\) both should be small
Explanation:
For making permanent magnet the retentivity \(OQ\) and coercive force \(OR\) must be large.
PHXII05:MAGNETISM and MATTER
360518
Core of electromagnet is made of ferromagnetic material which has
1 High retentivity
2 Low permeability
3 High permeability and low retentivity
4 None of the above
Explanation:
Conceptual Question
PHXII05:MAGNETISM and MATTER
360519
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
1 \(520\;A/m\)
2 \(1200\;A/m\)
3 \(2600\;A/m\)
4 \(285\;A/m\)
Explanation:
Coercivity of a bar magnet \(H = \frac{B}{{{\mu _0}}} = nI = \frac{N}{l}I\) \( = \frac{{100}}{{0.2}} \times 5.2 = 2600\;A/m\)
JEE - 2019
PHXII05:MAGNETISM and MATTER
360520
Hysteresis loops for two magnetic materials \(A\) and \(B\) are given below: These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use :
1 \(A\) for electromagnets and \(B\) for electric generators
2 \(A\) for transformers and \(B\) for electric generators
3 \(B\) for electromagnets and transformers
4 \(A\) for electric generators and transformers
Explanation:
For electromagnet and transformer, the coercivity should be low to reduce energy loss.
360517
The figure illustrates how \(B\) the flux density, inside a sample of ferromagnetic material varies with external magnetic field \(B_{o}\). For the sample to be suitable for making a permanent magnet
1 \(OQ\) should be large, \(OR\) should be small
2 \(OQ\) and \(OR\) both should be large
3 \(OQ\) should be small and \(OR\) should be large
4 \(OQ\) and \(OR\) both should be small
Explanation:
For making permanent magnet the retentivity \(OQ\) and coercive force \(OR\) must be large.
PHXII05:MAGNETISM and MATTER
360518
Core of electromagnet is made of ferromagnetic material which has
1 High retentivity
2 Low permeability
3 High permeability and low retentivity
4 None of the above
Explanation:
Conceptual Question
PHXII05:MAGNETISM and MATTER
360519
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
1 \(520\;A/m\)
2 \(1200\;A/m\)
3 \(2600\;A/m\)
4 \(285\;A/m\)
Explanation:
Coercivity of a bar magnet \(H = \frac{B}{{{\mu _0}}} = nI = \frac{N}{l}I\) \( = \frac{{100}}{{0.2}} \times 5.2 = 2600\;A/m\)
JEE - 2019
PHXII05:MAGNETISM and MATTER
360520
Hysteresis loops for two magnetic materials \(A\) and \(B\) are given below: These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use :
1 \(A\) for electromagnets and \(B\) for electric generators
2 \(A\) for transformers and \(B\) for electric generators
3 \(B\) for electromagnets and transformers
4 \(A\) for electric generators and transformers
Explanation:
For electromagnet and transformer, the coercivity should be low to reduce energy loss.
