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 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 : 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 : 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 : 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 : 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 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
Description : Magnetic flux linked with a coil can be changed by using an: a. Permanent magnet b.Bar magnet c. Electromagnet d. Horseshoe magnet
Last Answer : b.Bar magne
Description : When a conductor cuts magnetic flux, an emf is induced in the conductor. This is known as (a) Joule's law (b) Faraday's law (c) Coulomb's law (d) Ampere’s law
Last Answer : 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 ... 2. Magnitude of induced e.m.f. is directly proportional to rate of change of flux linkage.
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
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 : The phenomenon of producing emf in the coil due to change of current in the coil itself is called: a. mutual induction b. self-induction c. self-inductance d. mutual inductance
Last Answer : d. mutual inductance
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 magnetic flux φB through a plane element of area A⃗ in a uniform magnetic field B⃗⃗ is minimum at a) θ = 900 b) θ = 00 c) θ = 1800 d) None of these
Last Answer : a) θ = 900
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
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 : 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 : 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.
Description : Please ripley me due to emergency
Last Answer : To calculate the flux density in the ring, you need to use the following formula: B = (μ * I * N) / (2 * π * r) where: B is the flux density in the ring (in teslas) μ is the relative permeability ... 2 * π * 0.127 m) = 0.53 T So the flux density in the ring would be approximately 0.53 teslas.
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 : 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 : Which of the following is a vector quantity ? (a) Relative permeability (b) Magnetic field intensity (c) Flux density (d) Magnetic potential
Last Answer : (b) Magnetic field intensity
Description : In motor a permanent magnet provides: a. Electric field b. electric flux c. magnetic field d. gravitational field
Last Answer : d. gravitational field
Description : Which of the following does not equal the unit of magnetic flux density? a) 1 Wbm-2 b) 1 NA-1m -1 c) Both (a) and (b) d) 1 Wbm-1
Last Answer : d) 1 Wbm-1
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 space around the charge within which other charges are influenced by it is called: (a) Electric field (b) Magnetic field (c) Electric flux (d) Electric intensity
Last Answer : a) Electric field
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 : 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 : Calculate the emf of a coil with turns 100 and flux rate 5 units. a) 20 b) -20 c) 500 d) -500
Last Answer : d) -500
Description : Calculate the emf when a coil of 100 turns is subjected to a flux rate of 0.3 tesla/sec. a) 3 b) 30 c) -30 d) -300
Last Answer : c) -30
Description : The windings of the electromagnetic are usually called: a. Magnetic coils b. Field coil c. Electric coil d. simple coil
Last Answer : c. Electric coil
Description : When a uniform magnetic field B is applied to a current carrying coil, the coil will rotate in such a manner that its plane a) becomes parallel to B b) becomes anti-parallel to B c) makes an angle of 600 with B d) becomes perpendicular to B
Last Answer : d) becomes perpendicular to B
Description : The pole faces of U-shaped magnet in a moving coil galvanometer are made concave to a) decrease the strength of magnetic field b) create a non-uniform magnetic field c) make the magnetic field radial d) All of these
Last Answer : c) make the magnetic field radial
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.
Description : The number of electric field lines passing through a certain element of area is called: (a) Electric lines of force (b) Electric intensity (c) Electric flux (d) None of these
Last Answer : (c) Electric flux
Description : When field is parallel to plane of area, magnetic flux through coil isA. zero B. infinite C. 2 D. 5
Last Answer : zero
Description : E.M.F for a coil depends upon A. the cross sectional area B. no. of turns of wire C. the magnitude of magnetic flux density D. all of above
Description : Find the total flux in a coil of magnetic flux density 12 units and area 7 units. a) 0.84 b) 0.96 c) 8.4 d) 9.6
Last Answer : a) 0.84
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 : When a motor is just started, back emf is almost ______: a. Infinite b. zero c. minimum d. maximum
Last Answer : d. maximum
Description : If the motor is overloaded, then the magnitude of ‘back emf’” a. Increases b. Decreases c. Constant d. Becomes zero
Last Answer : Increases
Description : Terminal potential difference of a battery is greater than its emf when a. the internal resistance of battery is infinite b. the internal resistance of battery is zero c. the battery is charged d. the battery is discharged
Last Answer : c. the battery is charged
Description : A neon flashlight cell with an emf of 1.5V gives a current of 15A when connected directly to an ammeter of resistance 0.04?. Internal resistance of the cell is a. 0.0004? b. 0.06? c. 0.10? d. 0.13?
Last Answer : b. 0.06?
Description : The inductance is the measure of a) Electric charges stored by the material b) Emf generated by energising the coil c) Magnetic field stored by the material d) Magnetization of dipoles
Last Answer : c) Magnetic field stored by the material
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