1 |
In AC system we generate sine wave form because: |
It san be easily draw
It produces least disturbance in electrical circuits
It is nature standard
Other waves cannot be produced easily
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2 |
In an LRC circiut, the capacitance is made one-fourth, when an resonance . Then what should be change in inductance, so that the circuit remain in resonance? |
4 times
1/4 times
8 times
2 times
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3 |
In chopke coil the resistance XL an resistance R are: |
X<sub>L</sub>=R
X<sub>L</sub><<R
X<sub>L</sub>>>R
X<sub>L</sub>=<span style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;">∞</span>
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4 |
The peak value of alternating current is 5√2 A. The mean square value of current will be: |
5A
2.5A
5<b style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;">√2A</b>
5<sup>2</sup>
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5 |
The peak value of alternating current is 5√2 A. The mean square value of current will be: |
5A
2.5A
5<b style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 16px;">√2A</b>
5<sup>2</sup>
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6 |
A capacitor is perfectly insulator for: |
Direct current
Alternating current
Direct as well as alternating current
None of these
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7 |
The AC system is preferred to DC system because: |
AC voltage can be easily changed in magnitude
DC motor angular velocity is affected badly
High voltage AC transmission is less efficient
Domestic appliance require AC voltage for their operation
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8 |
In Series resonance circuit the impedance of circuit art resonance frequency, is |
Maximum
Minimum
It is unequal to R
None of above
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9 |
The resonance frequency is given by: |
fr = 2π√LC
fr = 1/2πLC
fr = 1/ 2π√LC
f1 = 1/ 2πC√L
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10 |
The condition of resonance is: |
XL = 1/2 Xc
X<sub>L</sub> = X<sub>c</sub>
X<sub>c</sub> = 4<sub>x2</sub>
None of above
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11 |
Power dissipation in A.C circuit is expressed as: |
P =I<sub>rms</sub> x V<sub>rms</sub> Sinθ
IxVCosθ
I<sub>rms</sub>xV<sub>rms</sub>Cosθ
I<sub>rms</sub> x V<sub>rms</sub> Sin2θ
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12 |
Power dissipation is a pure inductive or in a pure capacitance circuit is: |
10<sup>6</sup>
0
10<sup>∘</sup>
Maximum
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13 |
Unit of impedance is: |
Ohm
Ohm<sup>-1</sup>
no unit
Ohm m<sup>-1</sup>
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14 |
Impedance is denoted by: |
A
Z
P
Q
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15 |
The combined effect of resistance and reactance in circuit is called: |
Impedance
Inductance
Capacitance
None of above
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16 |
XL= |
2πfL
1/2πfL
2πfL
fL/2π
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17 |
In A.C circuit of inductor which one is true |
Voltage leads current by phase angle π/2
Voltage lags current by π/2
Current leads voltage by π/2
Both remain in phase
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