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Q1. | A coil is wound on iron core which carries current I. The self induced voltage in the coil is not affected by |

A. | variation in coil current [Wrong Answer] |

B. | variation in voltage to the coil [Correct Answer] |

C. | change of number of turns of coil [Wrong Answer] |

D. | the resistance of magnetic path [Wrong Answer] |

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

⇒ An averaVoltage of 10 V is induced in a 250 turns solenoid as a result of a change in flux which occurs in 0.5 second. The total flux change is

20 Wb

2 Wb

0.2 Wb

0.02 Wb

⇒ The co-efficient of self-inductance for a coil is given as

NI/Φ

NΦ/I

NI

^{2}/Φ

NΦ/I

^{2}

⇒ 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

⇒ 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

⇒ A 200 turn coil has an inductance of 12 mH. If the number of turns is increased to 400 turns, all other quantities (area, length etc.) remaining the same, the inductance will be

6 mH

14 mH

24 mH

48 mH

⇒ Both the number of turns and the core length of an inductive coil are doubled. Its self-inductance will be

unaffected

doubled

halved

quadrupled

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

Air core

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⇒ 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

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⇒ Higher the self-inductance of a coil,

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lower the e.m.f. induced

greater the flux produced by it

longer the dela' in establishing steady current through it

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

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Inductance only

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Inductance and capacitance

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

Faraday

Lenz

Newton

Coulomb

⇒ Find the force acting on a conductor 3m long carrying a current of 50 amperes at right angles to a magnetic field having a flux density of 0.67 tesla.

100 N

400 N

600 N

1000 N

⇒ In case of an inductance, current is proportional to

voltage across the inductance

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both (a) and (b)

neither (a) nor (b)

⇒ 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

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6 mH

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⇒ 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

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

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mutual inductance

series aiding inductace

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

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⇒ 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?

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0.1 s

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5 s

⇒ 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

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⇒ In an iron cored coil the iron core is removed so that the coil becomes an air cored coil. The inductance of the coil will

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⇒ Which of the following is unit of inductance?

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⇒ As per Faraday's laws of electromagnetic induction, an e.m.f. is induced in a conductor whenever it

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⇒ 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

⇒ In case all the flux from the current in coil 1 links with coil 2, the co-efficient of coupling will be

2.0

1.0

0.5

zero

⇒ A coil is wound on iron core which carries current I. The self induced voltage in the coil is not affected by

variation in coil current

variation in voltage to the coil

change of number of turns of coil

the resistance of magnetic path

⇒ 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

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

induced current

charge

enery

induced e.m.f.