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Q1. | Which of the following inductor will have the least eddy current losses? |

A. | Air core [Correct Answer] |

B. | Laminated iron core [Wrong Answer] |

C. | Iron core [Wrong Answer] |

D. | Powdered iron core [Wrong Answer] |

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Explanation:-
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**Also Read Similar Questions Below :**

⇒ Which of the following statements is cotrect ?

The inductance of the coil carrying a constant D.C. current will change the current into pulses

The inductance of the coil carrying a constant D.C. current will increase the current

The inductance of the coil carrying a constant D.C. current will not affect the current

The inductance of the coil carrying a constant D.C. current will decrease the current

⇒ Which of the following inductor will have the least eddy current losses?

Air core

Laminated iron core

Iron core

Powdered iron core

⇒ Two coils have inductances of 8 mH and 18 mH and a co-efficient of coupling of 0.5. If the two coils are connected in series aiding, the total inductance will be

32 mH

38 mH

40 mH

48 mH

⇒ The core of a coil has a length of 200 mm. The inductance of coil is 6 mH. If the core length is doubled, all other quantities, remaining the same, the inductance will be

3 mH

12 mH

24 mH

48 mH

⇒ A crack in the magnetic path of an inductor will result in

unchanged inductance

increased inductance

zero inductance

reduced inductance

⇒ Current changing from 8 A to 12 A in one second induced 20 volts in a coil. The value of inductance is

5 mH

10 mH

5 H

10 H

⇒ Air-core coils are practically free from

hysteresis losses

eddy current losses

both (a) and (b)

none of the above

⇒ Which of the following circuit element stores energy in the electromagnetic field?

Inductance

Condenser

Variable resistor

Resistance

⇒ Two 300 µH coils in series without mutual coupling have a total inductance of

300 µH

600 µH

150 µH

75 µH

⇒ A coil induces 350 mV when the current changes at the rate of 1 A/s. The value of inductance is

3500 mH

350 mH

250 mH

150 mH

⇒ The direction of induced e.m.f. can be found by

Laplace's law

Lenz's law

Fleming's right hand rule

Kirchhoffs voltage law

⇒ A 500 turns solenoid develops an average induced voltage of 60 V. Over what time interval must a flux change of 0.06 Wb occur to produce such a voltage?

0.01 s

0.1 s

0.5 s

5 s

⇒ Which of the following circuit elements will oppose the change in circuit current?

Capacitance

Inductance

Resistance

All of the above

⇒ Which circuit element(s) will oppose the change in circuit current?

Resistance only

Inductance only

Capacitance only

Inductance and capacitance

⇒ The magnitude of the induced e.m.f. in a conductor depends on the

flux density of the magnetic field

amount of flux cut

amount of flux linkages

rate of change of flux-linkages

⇒ In case of an inductance, current is proportional to

voltage across the inductance

magnetic field

both (a) and (b)

neither (a) nor (b)

⇒ A conductor 2 metres long moves at right angles to a magnetic field of flux densit 1 tesla with a velocity of 12.5 m/s. The induced e.m.f. in the conductor will be

10 V

15 V

25 V

50 V

⇒ The law that the induced e.m.f. and current always oppose the cause producing them is due to

Faraday

Lenz

Newton

Coulomb

⇒ The self inductances of two coils are 8 mH and 18 mH If the co-efficients of coupling is 0.5, the mutual inductance of the coils is

4 mH

5 mH

6 mH

12 mH

⇒ Which of the following is unit of inductance?

Ohm

Henry

Ampere turns

Webers/metre

⇒ A laminated iron core has reduced eddy-current losses because

more wire can he used with less D.C. resistance in coil

the laminations are insulated from each other

the magnetic flux is concentrated in the air gap of the core

the laminations are stacked vertically

⇒ Higher the self-inductance of a coil,

lesser its weher-turns

lower the e.m.f. induced

greater the flux produced by it

longer the dela' in establishing steady current through it

⇒ Two coils have self-inductances of 10 H and 2 H, the mutual inductance being zero. If the two coils are connected in series, the total inductance will be

6 H

8 H

12 H

24 H

⇒ A conductor carries 125 amperes of current under 60° to a magnetic field of 1.1 tesla. The force on the conductor will be nearly

50 N

120 N

240 N

480 N

⇒ A coil with negligible resistance has 50 V across it with 10 mA. The inductive reactance is

50 ohms

500 ohms

1000 ohms

5000 ohms

⇒ An e.m.f. of 16 volts is induced in a coil of inductance 4 H. The rate of change of current must be

64 A/s

32 A/s

16 A/s

4 A/s

⇒ For a purely inductive circuit which of the following is true ?

Apparent power is zero

Relative power is zero

Actual power of the circuit is zero

Any capacitance even if present in the circuit will not be charged

⇒ The property of coil by which a counter e.m.f. is induced in it when the current through the coil chatiges is known as

self-inductance

mutual inductance

series aiding inductace

capacitance

⇒ Lenz's law is a consecluence of the law of conservation of

induced current

charge

enery

induced e.m.f.

⇒ Mutually inductance between two magnetically-coupled coils depends on

permeability of the core

the number of their turns

cross-sectional area of their common core

all of the above