When a conductor cuts magnetic flux, an emf is induced in the conductor. This is known as Faraday's law.
There are two Faraday's law of electromagnetic induction.
1. Changing flux produces emf in a conductor
2. Magnitude of induced e.m.f. is directly proportional to rate of change of flux linkage.
Description : Which of the following will produce an induced emf: a. Changing area of coil b. Changing magnetic flux c. changing orientation of coil d. all of them
Last Answer : c. changing orientation of coil
Description : The current flowing in a coil due to induced emf depends upon: a. shape of coil b. resistance of coil c. area of coil d. magnetic flux
Last Answer : a. shape of coil
Description : The induced emf is produced in a circuit due to: a. Initial magnetic flux b. final magnetic flux c. Change of magnetic flux d. constant magnetic flux
Last Answer : d. constant magnetic flux
Description : The current in ampere through an inductor is i(10+20t) Here t is in second. The induced emf in the inductor 4V. Total flux linked with the inductor at
Last Answer : The current in ampere through an inductor is i(10+20t) Here t is in second. The induced emf in the inductor 4V. ... 10 Wb B. 20 Wb C. 30 Wb D. 40 Wb
Description : Find the emf induced in a coil of 60 turns with a flux rate of 3 units. a) -60 b) -180 c) 60 d) 180
Last Answer : b) -180
Description : The induced emf in a material opposes the flux producing it. This is a) Faraday law b) Ampere law c) Lenz law d) Curie law
Last Answer : c) Lenz law
Description : The emf 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 : (C) leads the flux by 90 degree.
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.
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
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
Description : The greatest induced EMF will occur in a straight wire moving at constant speed through a uniform magnetic field when the angle between the direction of the wire's motion and the direction of the magnetic field is w) 0 degrees x) 30 degrees y) 60 degrees z) 90 degrees
Last Answer : ANSWER: Z -- 90 DEGREES
Description : If velocity of a conductor moving through a magnetic field ‘B’ is made zero, then Motional emf will be: a. –VBL b. –V/BL c. – BL/V d. zero
Last Answer : a. –VBL
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
Description : For a straight wire, induced current depends uponA. the speed of movement of wire B. the length of wire C. the magnitude of magnetic flux density D. all of above
Last Answer : all of above
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
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
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
Description : Self induced emf and Mutually induced emf
Last Answer : (i) Self-induced e.m.f.: The e.m.f. induced in a coil due to the change of its own flux linked with it, is called self-induced e.m.f. (ii) Mutually induced e.m.f.: The e.m.f. induced in a coil due to the changing current in the neighbouring coil, is called mutually induced e.m.f.
Description : Compare statically induced emf with dynamically induced emf on any four points.
Last Answer : Statically induced emf Dynamically induced emf Emf is induced without any relative motion between conductor and magnetic field. Emf is induced due to relative motion between conductor ... induced in transformer windings e.g emf induced in Generator, Alternator armature windings
Description : Define: 1) statically induced EMF 2) dynamically induced EMF Write the names of equipments in which these two types of EMF get induced
Last Answer : Concept of statically induced emf: The emf induced in coil or conductors without any relative motion between it and magnetic field is called statically induced emf. When conductor is stationary and flux ... it. This emf is dynamically induced emf. e.g. Emf induced in generators, alternator.
Description : List the two types of induced EMF.
Last Answer : There are two types of EMF one is statically induced EMF and second is dynamically induced EMF.
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
Description : If the magnetic flux density and current are at right angles, then component of force acting on the conductor is A. BIL cosθ B. BIL sinθ C. BIL tanθ D. BL sinθ
Last Answer : BIL sinθ
Description : Find the Lorentz force due to a conductor of length 2m carrying a current of 1.5A and magnetic flux density of 12 units. a) 24 b) 36 c) 32 d) 45
Last Answer : c) 32
Description : Find the magnetic flux density of a finite length conductor of radius 12cm and current 3A in air( in 10 -6 order) a) 4 b) 5 c) 6 d) 7
Last Answer : b) 5
Description : Find the force on a conductor of length 12m and magnetic flux density 20 units when a current of 0.5A is flowing through it. a) 60 b) 120 c) 180 d) 200
Last Answer : b) 120
Description : Fleming's left hand rule is used to find (a) direction of magnetic field due to current carrying conductor (b) direction of flux in a solenoid (c) direction of force on a current carrying conductor in a magnetic field (d) polarity of a magnetic pole
Last Answer : (c) direction of force on a current carrying conductor in a magnetic field
Description : ___________ is not affected by a magnetic field a) Change in magnetic flux b) a moving electron c) a stationary proton d) current flowing in a conductor
Last Answer : c) a stationary proton
Description : The induced current in transformer which produced in the direction perpendicular to flux, is known as: a. Conventional current b. electronic current c. Perpendicular current d. Eddy current
Last Answer : c. Perpendicular current
Description : The current in ampere through an inductor is i(10+20t) Here t is in second. The induced emf in the inductor 4V. The self inductance of the indicator i
Last Answer : The current in ampere through an inductor is i(10+20t) Here t is in second. The induced emf in the inductor 4V. The ... B. `0.4` C. `0.1` D. `1.0`
Description : Write down the equation for frequency of emf induced in an Altenator.
Last Answer : F = (PN)/120 Hz,Where P- Number of poles, N-Speed in rpm
Description : On what factors does the induced emf in the coil depend?
Last Answer : Induced e.m.f in a coil increases with increase in: a) the number of turns of the coil, b) the strength of the magnetic field c) the speed with which the magnet or the coil moves d) area of the coil
Description : What is the equation used to find out frequency of number of cycles of induced emf?
Last Answer : f = NP/120
Description : How we can find the direction of induced emf?
Last Answer : The direction of induced emf can be find out by the Fleming's right hand rule', and lenz's law' Fleming's right hand rule : Fleming's right hand rule states that, if ... that the action of magnetic field set up by induced current tends to opposes the root cause which produces it.
Description : Find the induced EMF in an inductor of 2mH and the current rate is 2000 units. a) 4 b) -4 c) 1 d) -1
Last Answer : b) -4
Description : What is meant by induced emf? By counter emf?
Last Answer : Induced emf is the emf which appears across a conductor when there is relative motion between the conductor and a magnetic field; counter emf is the emf induced in a conductor that opposes the applied voltage.
Description : Why is no emf induced in a rotating coil when it passes through the neutral plane?
Last Answer : No flux lines are cut.
Description : What rule should you use to determine the direction of induced emf in a coil?
Last Answer : The left-hand rule for generators.
Description : The direction of induced EMF can be found with the help of -
Last Answer : Lenz’s Law
Description : The phenomena of induced emf was observed by Faraday and Henry in: a. 1931 b. 1831 c. 1535 d. 1940
Last Answer : a. 1931
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
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
Description : 28.In a two winding transformer, the emf /turn in secondary winding is always......the induced emf power turn in primary A. equal to k times B. equal to 1/k times C. equal D. greater than
Last Answer : C. equal
Description : 6 In a two winding transformer, the primary and secondary induced emf E1 & E2 are always A. equal in magnitude B. anti phase with each other C. in phase with each other D. determined by load on transformer secondary
Last Answer : C. In phase with each other
Description : Slip of the induction machine is 0.02 and the stator supply frequency is 50 Hz. What will be the frequency of the rotor induced emf? (A) 10 Hz. (B) 50 Hz. (C) 1 Hz. (D) 2500 Hz.
Last Answer : Ans: C Given : s = 0.02 ; f = 50 Hz Therefore, frequency of rotor induced emf = s f = 0.02 x 50 = 1.0 Hz
Description : Explain statically induced EMF and Dynamically induced EMF with neat diagrams.
Last Answer : Statically Induced EMF:- When changing magnetic field links with a stationary coil an emf is induced. This emf is called statically induced emf. Statically induced EMF is of two types: Self-induced ... cuts the field and an emf is induced. This emf is called dynamically induced emf.
Description : List the types of induced emf.
Last Answer : The types of induced emf are : i) Statically induced emf , ii) Dynamically induced emf
Description : Define self induced Emf. Write equation of self induced Emf.
Last Answer : Definition: Self-induced emf is the e.m.f induced in the coil due to the change of flux produced by linking it with its own turns. Or Self induced emf is that which is induced in a coil, due to the change in its own current or flux. Self induced emf equation. E = - N (dΦ/dt) volts
Description : Define self and mutual induced emf.
Last Answer : Self-induced emf: Self-induced emf is the e.m.f induced in the coil due to the change of flux produced by linking it with its own turns. Mutual induced emf: The emf induced in a coil due to the change of flux produced by another neighbouring coil linking to it, is called Mutually Induced emf.
Description : Explain dynamic and static induced emf with neat diagram.
Last Answer : Dynamically Induced EMF:- In this case, either coil moves or magnet moves, so that there is relative motion between coil & magnetic field. Thus magnetic field is cut by coil & emf is induced in it. The emf ... The expression for induced EMF is e= -L(di/dt) or = -N(dϕ/dt).