Users Also Read

MCQ's Search Engine

Electrical Engineering

Mechanical Engineering

Civil Engineering

Automobile Engineering

Chemical Engineering

Computer Engineering

Electronics Engineering

Medical Science Engg

Q1. | The direction of induced e.m.f. can be found by |

A. | Laplace's law [Wrong Answer] |

B. | Lenz's law [Correct Answer] |

C. | Fleming's right hand rule [Wrong Answer] |

D. | Kirchhoffs voltage law [Wrong Answer] |

View Answer
Explanation:-
Answer : BDiscuss it below :!! OOPS Login [Click here] is required to post your answer/resultHelp other students, write article, leave your comments |

**Also Read Similar Questions Below :**

⇒ 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

⇒ 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

⇒ 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

⇒ 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

⇒ 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

⇒ Which of the following is unit of inductance?

Ohm

Henry

Ampere turns

Webers/metre

⇒ 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

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

unaffected

doubled

halved

quadrupled

⇒ 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

⇒ 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 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

⇒ In case of an inductance, current is proportional to

voltage across the inductance

magnetic field

both (a) and (b)

neither (a) nor (b)

⇒ 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

⇒ 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

increase

decrease

remain the same

initially increase and then decrease

⇒ 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

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

unchanged inductance

increased inductance

zero inductance

reduced inductance

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

Air core

Laminated iron core

Iron core

Powdered iron core

⇒ Air-core coils are practically free from

hysteresis losses

eddy current losses

both (a) and (b)

none of the above

⇒ 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

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

induced current

charge

enery

induced e.m.f.

⇒ An open coil has

zero resistance and inductance

infinite resistance and zero inductance

infinite resistance and normal inductance

zero resistance and high inductance

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

Faraday

Lenz

Newton

Coulomb

⇒ The co-efficient of coupling between two air core coils depends on

self-inductance of two coils only

mutual inductance between two coils only

mutual inductance and self inductance of two coils

none of the above

⇒ 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

⇒ 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

⇒ 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

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

300 µH

600 µH

150 µH

75 µH

⇒ Ifcurrentin a conductor increases then according to Lenz's law self-induced voltage will

aid the increasing current

tend to decrease the amount of current

produce current opposite to the increasing current

aid tite applied voltage

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

Inductance

Condenser

Variable resistor

Resistance