Q. The energy stored in a coil is 108 J. It is opened suddenly in 10 ms. The power dissipated instantaneously across the blades of switch is

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Q. A parallel RLC circuit with R1 = 20, L1 = 1/100 and C1 = 1/200 is scaled giving R2 = 10⁴, L2 = 10¯⁴ and C2, the value of C2 is

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Q. Thermistor has a positive temperature coefficient.

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Q. Assertion (A): The function Z(s) = 1/s² + 1 is not positive real.

Reason (R): The degrees of numerator and denominator differ by 2

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Q. Two sinusoidal voltage sources v1 = 50 sin (100t) and v1 = 50 sin (100t + p) are connected in parallel and fed an inductance XL = 2Ω. The cuirent through XL is

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Q. Two voltages 50 V each have a phase difference of 45°. The rms value of resultant sum of the two voltages is

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Q. Volt is equivalent to

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Q. A two branch parallel tuned circuit has a capacitance C in one of the two branches and resistance R in second branchs. As C is decreased the dynamic resistance

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Q. The frame of an electric motor is earthed through three earthing plates resistances 30 Ω, 20 Ω and 10 Ω respectively. During fault the energy dissipated by three plates are W1, W2 and W3. Then

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Q. Two voltages are 50 ∠0 V and 75 ∠ - 60° V. The sum of these voltages is

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Q. A magnetic circuit has an iron length of 20 cm and air gap length 0.1 cm. If μᵣ = 200 then

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Q. A circuit is fed by two sources of the same frequency and values 100 ∠0° V and 20 ∠30°V. The current in a particular branch is 5 ∠19° A. If the magnitudes of the sources and changed to 200 ∠0° V and 40 ∠30° V, the current in that branch should be

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Q. Two coils X and Y have self inductances of 5 mH and 10 mH and mutual inductance of 3 mH. If the current in coils X change at a steady rate of 100 A/s, the emf induced in coil Y is

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Q. Two capacitors of 2 μF and 4 μF capacitance are connected in series across a 30 V dc battery. After the capacitors have been charged, the voltage across them will be

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Q. A 50 Hz current has an amplitude of 10 A. The rate of change of current at t = 0.005 after i = 0 and is increasing is

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Q. In an air cored coil, a current of 0.7 A causes a flux of 5 x 10^-6 Wb. If the core is made of cast iron and the coil is similar, the same current can set up a flux of about

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Q. The self inductances of two coils are 27 H and 3 H. If the winding or coils is such that 50% of flux of one links the other, the mutual inductance is

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Q. In a lead acid cell, the positive plate has spongy lead.

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Q. For H(s) to be positive real, the condition Re[H(jω)] ≥ 0 for 0 ≤ ω ≤ ∞ is

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Q. A parallel plate capacitor with air as dielectric has a capacitance C. If the dielectric has a dielectric constant ∈ᵣ and the remaining dimensions are the same, the capacitance will be

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