For the production of induced e.m.f. field system of an electric machine_________.

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Answer :

For the production of induced e.m.f. field system of an electric machine may be on stator or rotor.

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Related questions

The left hand rule correlates to (a) current, induced e.m.f. and direction of force on a conductor (b) magnetic field, electric field and direction of force on a conductor (c) self induction, mutual induction and direction of force on a conductor (d) current, magnetic field and direction of force on a conductor

Description : The left hand rule correlates to (a) current, induced e.m.f. and direction of force on a conductor (b) magnetic field, electric field and direction of force on a conductor (c) self induction, ... and direction of force on a conductor (d) current, magnetic field and direction of force on a conductor

Last Answer : (d) current, magnetic field and direction of force on a conductor

Which of the following quantity maintains the same direction whether a D.C. machine runs as a generator or as a motor a. Induced e.m.f. b. Armature Current c. Field Current d. Supply Current

Description : Which of the following quantity maintains the same direction whether a D.C. machine runs as a generator or as a motor a. Induced e.m.f. b. Armature Current c. Field Current d. Supply Current  

Last Answer : Which of the following quantity maintains the same direction whether a D.C. machine runs as a generator or as a motor a. Induced e.m.f. b. Armature Current c. Field Current d. Supply Current  

A straight wire of length 0.20 m moves at a steady speed of 3.0 m s-1 at right angles to the magnetic field of flux density 0.10 T. The e.m.f induced across ends of wire is A. 0.5 V B. 0.06 V C. 0.05 V D. 0.04 V

Description : A straight wire of length 0.20 m moves at a steady speed of 3.0 m s-1 at right angles to the magnetic field of flux density 0.10 T. The e.m.f induced across ends of wire is A. 0.5 V B. 0.06 V C. 0.05 V D. 0.04 V

Last Answer : 0.06 V

Which law states that induced e.m.f and current always opposes the cause producing them?

Description : Which law states that induced e.m.f and current always opposes the cause producing them?

Last Answer : Lenz's law states that induced e.m.f and current always opposes the cause producing them.

These self inductance of a circuit is defined as twice the work done against the induced e.m.f.

Description : These self inductance of a circuit is defined as twice the work done against the induced e.m.f. on establishing unit current in the coil. If the current to be established in the coil is doubled, the work done ... induced e.m.f. will be  1. Doubled  2. Halved  3. four times  4. Quarter times 

Last Answer : These self inductance of a circuit is defined as twice the work done against the induced e.m.f. on establishing unit current in the coil. If the current to be established in the coil is doubled, the work done against the induced e.m.f. will be four times

The e.m.f. induced in the primary of a transformer: ...

Description : The e.m.f. induced in the primary of a transformer:  (A) is in phase with the flux (B) lags behind the flux by 90 degree (C) leads the flux by 90 degree (D) is in phase opposition to that of flux

Last Answer : The e.m.f. induced in the primary of a transformer: leads the flux by 90 degree 

What is the direction of the induced electric field?

Description : What is the direction of the induced electric field?

Last Answer : It  is  in  opposite  direction   to  the  one  that   produced  it.

Mention the factors on which the magnitude of the e.m.f induced in the transformer depends.

Description : Mention the factors on which the magnitude of the e.m.f induced in the transformer depends.

Last Answer : 1) E.m.f in the primary coil 2) Number of turns in the primary coil 3) Number of turns in the secondary coil 4) The core material

Magnitude of induced e.m.f is proportional to A. rate of change of current B. rate of change of voltage C. rate of change of magnetic flux linkage D. rate of change of resistance

Description : Magnitude of induced e.m.f is proportional to A. rate of change of current B. rate of change of voltage C. rate of change of magnetic flux linkage D. rate of change of resistance

Last Answer : rate of change of magnetic flux linkage

E.M.F can be induced in a circuit by A. changing magnetic flux density B. changing area of circuit C. changing the angle D. all of above

Description : E.M.F can be induced in a circuit by A. changing magnetic flux density B. changing area of circuit C. changing the angle D. all of above

Last Answer : all of above

The introduction of interpoles in between the main pole improves the performance of d.c. machines, because (A) The interpole produces additional flux to augment the developed torque. (B) The flux waveform is improved with reduction in harmonics. (C) The inequality of air flux on the top and bottom halves of armature is removed. (D) A counter e.m.f. is induced in the coil undergoing commutation.

Description : The introduction of interpoles in between the main pole improves the performance of d.c. machines, because (A) The interpole produces additional flux to augment the developed torque. (B) The flux waveform is ... armature is removed. (D) A counter e.m.f. is induced in the coil undergoing commutation.

Last Answer : Ans: D Counter e.m.f is produced, it neutralizes the reactive emf.

The voltage regulation of an alternator having 0.75 leading p.f. load, no-load induced e.m.f. of 2400V and ...

Description : The voltage regulation of an alternator having 0.75 leading p.f. load, no-load induced e.m.f. of 2400V and rated terminal voltage of 3000V is —————————————  A) 20% B) —20% C) 150 D) -26.7

Last Answer : -20

When a magnet is in motion relative to a coil the induced e.m.f. does not depend upon

Last Answer : When a magnet is in motion relative to a coil the induced e.m.f. does not depend upon resistance of the coil.

The induced e.m.f. in the armature conductors of a d.c. motor is?

Description : The induced e.m.f. in the armature conductors of a d.c. motor is?

Last Answer : The induced e.m.f. in the armature conductors of a d.c. motor is sinusoidal.

If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be?

Description : If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be?

Last Answer : If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be zero.

In any rotating machine that part which houses the conductors and in which e.m.f. induced is to be utilised is called?

Last Answer : In any rotating machine that part which houses the conductors and in which e.m.f. induced is to be utilised is called armature.

The e.m.f. induced in the armature of a shunt generator is 600 V. The armature resistance is 0.1 ohm...

Description : The e.m.f. induced in the armature of a shunt generator is 600 V. The armature resistance is 0.1 ohm. If the armature current is 200 A, the terminal voltage will be?

Last Answer : The e.m.f. induced in the armature of a shunt generator is 600 V. The armature resistance is 0.1 ohm. If the armature current is 200 A, the terminal voltage will be 580 V.

If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by?

Last Answer : If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by Blv.

While applying Fleming's right-hand rule to And the direction of induced e.m.f., the thumb points towards?

Last Answer : While applying Fleming's right-hand rule to And the direction of induced e.m.f., the thumb points towards direction of motion of conductor, if forefinger points along the lines of flux.

Fleming's right-hand rule regarding direction of induced e.m.f., correlates?

Last Answer : Fleming's right-hand rule regarding direction of induced e.m.f., correlates magnetic flux, direction of motion and the direction of e.m.f. induced.

According to Fleming's right-hand rule for finding the direction of induced e.m.f...

Description : According to Fleming's right-hand rule for finding the direction of induced e.m.f., when middle finger points in the direction of induced e.m.f., forefinger will point in the direction of?

Last Answer : According to Fleming's right-hand rule for finding the direction of induced e.m.f., when middle finger points in the direction of induced e.m.f., forefinger will point in the direction of lines of force.

When the armature of a D.C. motor rotates, e.m.f. induced is

Last Answer : When the armature of a D.C. motor rotates, e.m.f. induced is back e.m.f.

An advantage of optic fiber rejecting an induced noise signals from magnetic field or solar storms flux. A. Electric hazard B. Cross talk C. Immunity to noise D. Shielding

Description : An advantage of optic fiber rejecting an induced noise signals from magnetic field or solar storms flux. A. Electric hazard B. Cross talk C. Immunity to noise D. Shielding

Last Answer : C. Immunity to noise

The induced voltage across a coil with 250 turns that is located in a magnetic field and is changing at a ...

Description : The induced voltage across a coil with 250 turns that is located in a magnetic field and is changing at a rate of 8 Wb/s is A. 1,000 V B. 2,000 V C.31.25 V D. 3,125 V

Last Answer : The induced voltage across a coil with 250 turns that is located in a magnetic field and is changing at a rate of 8 Wb/s is 2,000 V 

Double cross hybrid maize production technique was introduced by (A) G.H. Shull (B) Mendel (C) D.F.Jones (D) E.M.East

Description : Double cross hybrid maize production technique was introduced by (A) G.H. Shull (B) Mendel (C) D.F.Jones (D) E.M.East

Last Answer : (C) D.F.Jones

F = BIL can only be used if the magnetic field and electric current are A. at right angles to each other B. in same direction C. anti-parallel to each other D. anti-perpendicular to each other

Description : F = BIL can only be used if the magnetic field and electric current are A. at right angles to each other B. in same direction C. anti-parallel to each other D. anti-perpendicular to each other

Last Answer : at right angles to each other

: Moving a coil in and out of magnetic field induces A. force B. potential difference C. e.m.f D. voltage

Description : : Moving a coil in and out of magnetic field induces A. force B. potential difference C. e.m.f D. voltage

Last Answer : e.m.f

Total number of magnetic field lines passing through an area is called A. magnetic flux density B. magnetic flux C. e.m.f D. voltage

Description : Total number of magnetic field lines passing through an area is called A. magnetic flux density B. magnetic flux C. e.m.f D. voltage

Last Answer : magnetic flux

From which formula can the direction of induced electric current be determined ?

Description : From which formula can the direction of induced electric current be determined ?

Last Answer : : The direction of the induced electric current can be determined from Lenz's formula.

Give reason: Stationary coil and stationary magnet cannot produce induced electric current.

Description : Give reason: Stationary coil and stationary magnet cannot produce induced electric current.

Last Answer : An emf is induced in the coil only when there is relative motion between the coil and the magnet.

Give reason: In the experiment conducted by Faraday the induced electric current was not DC.

Description : Give reason: In the experiment conducted by Faraday the induced electric current was not DC.

Last Answer : The deflection in the galvanometer was to one side when the magnet was pushed in and the deflection was to opposite side when the magnet was taken out. Hence it was AC and not DC.

The resistance furnace produces heat by the (A) Electric arc struck between electrodes and the charge (B) Flow of current through a heating element (C) Combination of induced current and skin effect (D) None of these

Description : The resistance furnace produces heat by the (A) Electric arc struck between electrodes and the charge (B) Flow of current through a heating element (C) Combination of induced current and skin effect (D) None of these

Last Answer : (B) Flow of current through a heating element

The electric furnace in which heat is produced by a combination of induced current and skin effect is called __________ furnace. (A) Arc(B) Resistance(C) Low frequency induction(D) High frequency induction

Description : The electric furnace in which heat is produced by a combination of induced current and skin effect is called __________ furnace. (A) Arc (B) Resistance (C) Low frequency induction (D) High frequency induction

Last Answer : (D) High frequency induction

How can electric currents be induced with a coil and a magnet?

Description : How can electric currents be induced with a coil and a magnet?

Last Answer : by moving either the magnet or the coil

Induced electric currents can be explained using which of the following laws? w) Gauss's Law x) Faraday's Law y) Ohm's Law z) Ampere's Law

Description : Induced electric currents can be explained using which of the following laws? w) Gauss's Law x) Faraday's Law y) Ohm's Law z) Ampere's Law

Last Answer : ANSWER: X -- FARADAY'S LAW

The additional capital used per unit of additional production is called a. Induced investment b. Autonomous investment c. Incremental COR d. None of the above

Description : The additional capital used per unit of additional production is called a. Induced investment b. Autonomous investment c. Incremental COR d. None of the above

Last Answer : : c. Incremental COR COR refers to the number of units of capital required to produce one unit of output.

A charge q is moving with a velocity `v_(1)=1hati` m/s at a point in a magentic field and experiences a force `F=q[-hatj+1hatk]` N. If the charge is m

Description : A charge q is moving with a velocity `v_(1)=1hati` m/s at a point in a magentic field and experiences a force `F=q[-hatj+1hatk]` N. If the charge is m

Last Answer : A charge q is moving with a velocity `v_(1)=1hati` m/s at a point in a magentic field and experiences a force `F ... `(hat(i)+hat(j)-hat(k))Wb//m^(2)`

A 5 m ladder of mass 25 kg is placed in a position where its inclination to a vertical wall is at 30?. A 100 kg man is to climb the ladder. If the coefficient of static friction is 0.25 the height along ladder at which the slipping will be induced would be a.2.4 m b.1.6 m c.0.8 m d.1.2 m e.0.5 m

Description : A 5 m ladder of mass 25 kg is placed in a position where its inclination to a vertical wall is at 30?. A 100 kg man is to climb the ladder. If the coefficient of static friction is 0.25 the height along ladder at which the slipping will be induced would be a.2.4 m b.1.6 m c.0.8 m d.1.2 m e.0.5 m

Last Answer : c. 0.8 m

A rectangular coil of copper wires is rotated in a magnetic field. The direction of the induced current changes once in each -Physics-10

Description : A rectangular coil of copper wires is rotated in a magnetic field. The direction of the induced current changes once in each -Physics-10

Last Answer : half revolution When a rectangular coil is rotated in magnetic field, the direction of the induced current changes once in half revolution. As a result, the direction of the current in the coil remains the same. In text 13.7 Page:238

An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will __________. A. not affect the faulty generator due to the compensation of the other generators B. cause the slip rings to melt C. cause a low voltage differential to develop between the armature and the bus D. cause high currents to be induced in the field windings

Description : An AC generator operating in parallel loses its excitation without tripping the circuit breaker. This will __________. A. not affect the faulty generator due to the compensation of the other generators B. ... between the armature and the bus D. cause high currents to be induced in the field windings

Last Answer : Answer: D

Brush sparking during commutation may be caused by ________. A. eddy currents in the armature core B. laminations in the generator field pieces C. induced current opposite to coil inductance D. coil inductance discharge occurring at commutation

Description : Brush sparking during commutation may be caused by ________. A. eddy currents in the armature core B. laminations in the generator field pieces C. induced current opposite to coil inductance D. coil inductance discharge occurring at commutation

Last Answer : Answer: D

One of the generator or motor bearings is generally insulated from the end housing in order to prevent ________. A. rapid brush wear B. current leakage from the shaft C. excessive field winding heat D. circulation of shaft currents induced in the machine's frame

Description : One of the generator or motor bearings is generally insulated from the end housing in order to prevent ________. A. rapid brush wear B. current leakage from the shaft C. excessive field winding heat D. circulation of shaft currents induced in the machine's frame

Last Answer : Answer: D

The amount of voltage induced in the windings of an AC generator depends mainly on _____________. A. the number of field poles energized B. the speed at which the stator windings rotate through the magnetic field C. the strength of the magnetic field D. all of the above

Description : The amount of voltage induced in the windings of an AC generator depends mainly on _____________. A. the number of field poles energized B. the speed at which the stator windings rotate through the magnetic field C. the strength of the magnetic field D. all of the above

Last Answer : Answer: C

In a three-phase, squirrel-cage type, induction motor the rotating magnetic field is established by the _____________. A. current induced in the rotor windings B. application of a three-phase voltage supply to the stator windings C. laminated steel core and aluminum conductors in the rotor D. interaction of the magnetic field caused by the induced current in the squirrel-cage bars with the magnetic field of the stator

Description : In a three-phase, squirrel-cage type, induction motor the rotating magnetic field is established by the _____________. A. current induced in the rotor windings B. application of a three-phase voltage ... caused by the induced current in the squirrel-cage bars with the magnetic field of the stator

Last Answer : Answer: B

The amount of voltage induced in the windings of an AC generator depends on ____________. A. the number of conductors in series per winding B. the speed at which the magnetic field passes across the winding C. the strength of the magnetic field D. all of the above

Description : The amount of voltage induced in the windings of an AC generator depends on ____________. A. the number of conductors in series per winding B. the speed at which the magnetic field passes across the winding C. the strength of the magnetic field D. all of the above

Last Answer : Answer: D

The induced emf in a coil depends upon: a. Strength of magnetic field b. Resistance of the coil c. area of the coil d. All of them

Description : The induced emf in a coil depends upon: a. Strength of magnetic field b. Resistance of the coil c. area of the coil d. All of them

Last Answer : d. All of them

The induced current can be increased by: a. Using strong magnetic field b. moving loop faster c. Replacing loop by coil d. all of above

Description : The induced current can be increased by: a. Using strong magnetic field b. moving loop faster c. Replacing loop by coil d. all of above

Last Answer : d. all of above

In the plane of AC generator coil is parallel to the field, then emf induced in coil is: a. maximum b. minimum c. zero d. intermediate

Description : In the plane of AC generator coil is parallel to the field, then emf induced in coil is: a. maximum b. minimum c. zero d. intermediate

Last Answer : b. minimum

In the plane of the A.C generator coil is perpendicular to the field, then induced emf in the coil is: a. Maximum b. minimum c. zero d. intermediate value

Description : In the plane of the A.C generator coil is perpendicular to the field, then induced emf in the coil is: a. Maximum b. minimum c. zero d. intermediate value

Last Answer : b. minimum

A wire loop is moved parallel to a uniform magnetic field. The induced emf in the loop: a. depends on the shape b. depends on area c. depends on nature of loop d. zero

Description : A wire loop is moved parallel to a uniform magnetic field. The induced emf in the loop: a. depends on the shape b. depends on area c. depends on nature of loop d. zero

Last Answer : d. zero