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: 89 – 91.5
Q. The signal energy of the continuous-time signal x(t) = [(t -1) u(t -1)]-[(t – 2)u(t – 2)]-[(t – 3)u(t – 3)]+[(t – 4)u(t – 4)] is (A) 11/3 (B) 7/3 (C) 1/3 (D) 5/3 Ans: 5/3
The signal energy of the continuous-time signal Read More »
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
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
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
The number of roots of the polynomial, 𝑠7 + 𝑠6 + 7𝑠5 + 14𝑠4 + 31𝑠3 + 73𝑠2 + 25𝑠 + 200 Read More »
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:
The equivalent impedance Zeq for the infinite ladder circuit shown in the figure is Read More »
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
Q. Consider the two bus power system network with given loads as shown in the figure. All the values shown in the figure are in per unit. The reactive power supplied by generator G1 and G2 are QG1 and QG2 respectively. The per unit values of QG1, QG2, and line reactive power loss (Qloss) respectively
Consider the two bus power system network with given loads as shown in the figure Read More »
Q. The positive, negative and zero sequence impedances of a three phase generator are 𝑍1, 𝑍2 and 𝑍0 respectively. For a line-to-line fault with fault impedance 𝑍𝑓, the fault current is 𝐼𝑓1 = 𝑘𝐼𝑓, where 𝐼𝑓 is the fault current with zero fault impedance. The relation between 𝑍𝑓 and 𝑘 is Ans: Option A Sol:
The positive, negative and zero sequence impedances of a three phase generator are Read More »
