Source: http://www.allexamreview.com/2016/11/electrical-engineering-important-mcq_5.html
Timestamp: 2019-04-19 00:17:25+00:00

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indicated by symbol (V) in options.
E-HINTS is indicating the hints of answer.
B [ ]) Magnetic flux density.
C [ ]) Electric flux.
D [ ]) None of the above.
A [ ]) always straight.
C [ ]) sometimes curved.
D [ ]) none of above.
B [ ]) always parallel.
C [ ]) inclined at any angle.
A [ ]) Faradays law.
B [ ]) Kirchhoffs law.
C [ ]) Lenzs law.
A [ ]) proportional to d.
B [v]) inversely proportional to d.
D [ ]) none of abov.
60) Which field is associated with the capacitor?
C [ ]) Both of (1) and (2).
61) Which of the following expression is correct for electric field strength?
B [ ]) E = πD.
C [ ]) E = D² / ε.
D [v]) E = D / ε.
62) An equipotential surface is one which has all points at _____________ potential.
D [ ]) none of them.
C [ ]) reduce to zero.
D [ ]) remain unchanged.
A [v]) potential difference between electrodes.
B [ ]) resistivity of medium.
C [ ]) rate of change of potential difference.
D [ ]) rate of change of current.
A [ ]) increasing towards centre.
B [ ]) decreasing towards centre.
B [ ]) farad / meter.
A [ ]) electric charge density.
B [ ]) electric field intensity.
D [ ]) magnetic flux density.
A [v]) N / C.
B [ ]) N / Ampere.
D [ ]) 1 wb/m.
A [v]) V / d.
D [ ]) V × d.
71) A conductor of length l meters moves at right angles to a uniform magnetic field of flux density B = 1.5 T. if the velocity of revolution of the conductor is 50 ms-1 then induced e.m.f. in the conductor is 75 V.
B [ ]) 0 V.
C [ ]) 100 V.
D [ ]) 125 V.
A [ ]) relative permeability.
C [ ]) flux density.
74) Which of following is the unit of magnetic flux density?
A [ ]) core length increases.
B [ ]) core area increases.
C [v]) flux density increases.
D [ ]) flux density decreases.
78) Which of following is not a unit of flux?
D [ ]) All of above.
79) Which of following circuit element stores energy in electro – magnetic field?
A [ ]) flux linking with the coil is maximum.
B [ ]) rate of change of flux linkage is minimum.
C [v]) rate of change of flux linkage is maximum.
D [ ]) rate of cutting flux by coil sides is minimum.
A [ ]) 64 A / s.
B [ ]) 32 A / s.
C [ ]) 16 A / s.
D [v]) 4 A / s.
A [ ]) ampere / watt.
C [ ]) volt² / watt.
B [v]) G1 + G2 + G3.
C [ ]) 1 / G1 + 1 / G2 + 1 / G3.
A [ ]) high conductivity and low temperature coefficient.
B [v]) high conductivity and large temperature coefficient.
C [ ]) low conductivity and zero temperature coefficient.
D [ ]) low conductivity and high temperature coefficient.
85) If the three colour bands of a resistor are grey, violet and gold, what is the value of the resistor?
D [ ]) 9.7 ohms.
E [ ]) HINTS- The values of these colours are 8, 7 and multiplier of 0.1. Therefore, the value of resistance will be ( 87 X 0.1 ) = 8.7 ohms.
A [v]) voltage drops across both are same.
B [ ]) currents in both are same.
C [ ]) heat losses in both are same.
D [ ]) voltage drops are according to their resistive value.
D [ ]) nR .
E [ ]) HINTS-Length of the conductor becomes n times and at the same time cross section of the conductor becomes 1 / Nth times. Hence resistance of the conductor becomes n² times of its original value as length of the conductor is directly proportional and cross section is inversely proportional to the resistance.
88) Two equal resistors R connected in series across a voltage source V dissipate power P.What would be the power dissipated in the same resistors when they are connected in parallel across the same voltage source ?
E [ ]) HINTS-Say R is the resistance of the identical two resistors. When they are connected in series across a voltage source V, the equivalent resistance of the combination is 2R and then total power dissipated by the resistors will be P = V² / 2R. When they are connected in parallel across the same voltage source V, the equivalent resistance of the combination is R/2 then total power dissipated by the resistors will be V² / ( R / 2) = 4V² / 2R = 4P.
90) Three 3 Ω resistors are connected to form a triangle. What is the resistance between any two of the corner?
A [ ]) 9 Ω.
B [ ]) 6 Ω.
C [ ]) 3 Ω.
E [ ]) HINTS-Whenever we look at the said triangle from any two of its corners, we will find that it is just a parallel combination of one 3 Ω and one 6 Ω (3 + 3 = 6) resistor. Thus, the resistance across these two corner points of the triangle will be ( 3 X 6 )/ ( 3 + 6 ) = 18 / 9 = 2 Ω.
E [ ]) HINTS-The resistance of a conductor is directly proportional to its length and inversely proportional to its cross – sectional area. As the length and cross – sectional area both have become double, there will no change in resistance of the wire.
92) Resistance of which material does not change with change in temperature ?
B [v]) Metal alloys constantan and manganin.
93) Which of the following lamp has least resistance ?
A [v]) 200 W, 220 V.
C [ ]) 60 W, 220 V.
D [ ]) 25 W, 220 V.
Where, V is supply voltage and W is wattage rating of the lamp. From, above equation it is clear that, for fixed voltage source , resistance of an electric lamp is inversely proportional to its wattage rating. Here, 200 W, 220 V lamp has highest wattage rating, therefore its resistance will be least.
A [ ]) increase p.f of inductive load circuit.
B [ ]) to do phase split in AC 1 phase motor.
C [ ]) effect DC filter in electronic circuit.
D [v]) all of these.
A [ ]) there will be heavy current in the main line.
B [ ]) rest of two bulbs will not light.
D [v]) the other two bulbs will light.
C [ ]) remain constant.
D [ ]) none of these.
E [ ]) HINTS-If we remove a portion of resistance in that initial resistance, then the current resistance value will be decreased. This leads to flow more current than the previous case.Hence, according to the power equation (P = VI), if current increases then the power of the heater also increases.
A [ ]) 9 times.
B [v]) 1 / 9 times.
C [ ]) 3 times.
D [ ]) 1 / 3 times.
E [ ]) HINTS-If we connect three identical resistors, R in parallel, then the equivalent resistance is [ R / 3]. If we add that three [ R ] resistances in series, then the equivalent resistance is [ 3R ].Now the resultant resistance of the first combination to the second will be [ R / 3 ] / 3R = [ 1 / 9].

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