Q. In a series ac circuit a voltage of 20 V at 25 Hz causes a current of 0.20 A, while the same voltage at 75 Hz causes a current of 0.12 A. The circuit consists of

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Q. Elements R, L, C are connected in parallel and excited by a dc current I. If iR, iL and iC are the currents through R, L, C respectively then at t = 0

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Q. In a practical voltage source, the terminal voltage

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Q. The function of a choke in a fluorescent lamp is

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Q. A series resonant circuit is fed by a voltage having rms value V. At resonance, the voltage across inductance VL and voltage across capacitance VC are related as

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Q. In a series RLC circuit, R = 2 kΩ, L = 1H and C = µf/400. The resonant frequency is

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Q. Assertion (A): Millman's theorem helps in replacing a number of current sources in parallel by a single current source.

Reason (R): Maximum power transfer theorem is applicable only for dc, circuits.

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Q. Double integration of unit step function leads to

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Q. A conductor has a cylindrical shape with a diameter d. Its resistance is 2 Ω. It is recast into a cylindrical conductor of diameter 0.3d. The resistance of new conductor is likely to be

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Q. A constant k low pass T section filter has a characteristic impedance of 600 p at zero frequency. At f = fc the characteristic impedance is

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Q. Bus bars are always meant for very heavy currents.

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Q. A low-pass filter frequency responce H (jω) = A (ω) e^(jΦ) (ω) does not produce any phase distortion, if

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Q. In a tungsten filament lamp

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Q. An RLC series circuit has R = 8 Ω, XL = 8 Ω and XC = 8 Ω Its impedance is

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Q. Two similar mutually coupled coils have a total inductance of 900 mH and coefficient of coupling 0.5. The self inductance of each coils is

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Q. For a high pass filter attenuation = 0 at f = 0.

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Q. Two voltages are v1= 100 sin (ωt + 15°) and v2 = 60 cosωt, then

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Q. If A = 16 ∠64°, (A)^0.5 is

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Q. One commercial unit of energy is equal to

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Q. Two coupled coils with self inductances of 4 mH and 16 mH are connected in series. The maximum possible value of inductance can be

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