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Q. The voltage across the circuit in the figure, and the current through it, are given by the following expressions: 𝑣(𝑡) = 5 − 10 cos(𝜔𝑡 + 60°) V 𝑖(𝑡) = 5 + 𝑋 cos(𝜔𝑡) A where 𝜔 = 100 𝜋 radian/s. If the average power delivered to the circuit is zero, then the value of 𝑋 (in Ampere) ...

Q. The capacitance of an air-filled parallel-plate capacitor is 60 pF. When a dielectric slab whose thickness is half the distance between the plates, is placed on one of the plates covering it entirely, the capacitance becomes 86 pF. Neglecting the fringing effects, the relative permittivity of ...

Q. In the circuit shown in the figure, the bipolar junction transistor (BJT) has a current gain 𝛽 = 100. The base-emitter voltage drop is a constant, 𝑉𝐵𝐸 = 0.7 𝑉. The value of the Thevenin equivalent resistance 𝑅𝑇ℎ (in Ω) as shown in the figure is ___________(up to 2 decimal places). Ans: ...

Q. The signal energy of the continuous-time signal x(t) = --+ is (A) 11/3                      (B) 7/3                        (C) 1/3                       (D) 5/3 Ans: 5/3

Q.Digital input signals 𝐴, 𝐵, 𝐶 with 𝐴 as the MSB and 𝐶 as the LSB are used to realize the Boolean function 𝐹 = 𝑚0 + 𝑚2 + 𝑚3 + 𝑚5 + 𝑚7, where 𝑚𝑖 denotes the 𝑖𝑡ℎ minterm. In addition, 𝐹 has a don’t care for 𝑚1. The simplified expression for 𝐹 is given by Ans: Option B

Q. Which one of the following statements is true about the digital circuit shown in the figure A. It can be used for dividing the input frequency by 3. B. It can be used for dividing the input frequency by 5. C. It can be used for dividing the input frequency by 7. D. It cannot be ...

Q. The number of roots of the polynomial, 𝑠7 + 𝑠6 + 7𝑠5 + 14𝑠4 + 31𝑠3 + 73𝑠2 + 25𝑠 + 200, in the open left half of the complex plane is (A) 3 (B) 4 (C) 5 (D) 6 Ans: 3

Q. The equivalent impedance Zeq for the infinite ladder circuit shown in the figure is (A) j12 Ω                    (B) –j12 Ω                  (C) j13 Ω                   (D) 13 Ω Ans: j12Ω Sol:

Q. A DC voltage source is connected to a series L-C circuit by turning on the switch S at time t = 0 as shown in the figure. Assume i(0) = 0, v(0) = 0 . Which one of the following circular loci represents the plot of i(t) versus v(t) ? Ans: Option B

Q. The per-unit power output of a salient-pole generator which is connected to an infinite bus, is given by the expression, 𝑃 = 1.4 sin 𝛿 + 0.15 sin 2𝛿, where 𝛿 is the load angle. Newton- Raphson method is used to calculate the value of 𝛿 for 𝑃 = 0.8 pu. If the initial guess is 30°, then its value ...