Recent questions tagged numerical-answers

A three-phase, $50 Hz$ salient-pole synchronous motor has a per-phase direct-axis reactance $(X_{d})$ of $0.8$ pu and a per-phase quadrature-axis reactance $(X_{q})$ of $...

A single-phase $400 V, 50 Hz$ transformer has an iron loss of $5000 W$ at the rated condition. When operated at $200 V, 25 Hz$, the iron loss is $2000 W$. When operated a...

A $30 MVA$, $3$-phase, $50 Hz$, $13.8 kV$, star-connected synchronous generator has positive, negative and zero sequence reactances, $15\%$, $15\%$ and $5\%$ respectively...

A $DC$ shunt generator delivers $45 A$ at a terminal voltage of $220 V$. The armature and the shunt field resistances are $0.01 \Omega$ and $44 \Omega$ respectively. The ...

The voltage $(v_{s})$ across and the current $(i_{s})$ through a semiconductor switch during a turn-ON transition are shown in figure. The energy dissipated during the tu...

The switches $T1$ and $T2$ in Figure (a) are switched in a complementary fashion with sinusoidal pulse width modulation technique. The modulating voltage $v_{m}(t)=0.8\si...

A three-phase cable is supplying $800 kW$ and $600 kVAr$ to an inductive load. It is intended to supply an additional resistive load of $100 kW$ through the same cable wi...

In the circuit shown, switch $S_{2}$ has been closed for a long time. At time $t=0$ switch $S_{1}$ is closed. At $t=0^{+}$, the rate of change of current through the indu...

Candidates were asked to come to an interview with $3$ pens each. Black, blue, green and red were the permitted pen colours that the candidate could bring. The probabilit...

Given the following polynomial equation $s^{3}+5.5 s^{2}+8.5s+3=0$ the number of roots of the polynomial, which have real parts strictly less than $−1$, is ________.

Consider the following state-space representation of a linear time-invariant system.$x(t)=\begin{pmatrix}1&0 \\0&2\end{pmatrix}x(t), y(t)= c^{T} x(t), c =\begin{pmatrix}1...

Let $S=\sum_{n=0}^{\infty} n\alpha^{n}$ where $\mid \alpha \mid < 1$. The value of $\alpha$ in the range $0 < \alpha < 1$, such that $S=2 \alpha$ is _________.

A steady dc current of $100$ $A$ is flowing through a power module $(S, D)$ as shown in Figure (a). The $V-I$ characteristics of the $IGBT (S)$ and the diode $(D)$ are sh...

A buck converter, as shown in Figure (a) below, is working in steady state. The output voltage and the inductor current can be assumed to be ripple free. Figure (b) shows...

The magnitude of three-phase fault currents at buses $A$ and $B$ of a power system are $10$ pu and $8$ pu, respectively. Neglect all resistances in the system and conside...

In the given circuit, the current supplied by the battery, in ampere, is ________.

In the portion of a circuit shown, if the heat generated in $5 \Omega$ resistance is $10$ calories per second, then heat generated by the $4 \Omega$ resistance, in calori...

A soft-iron toroid is concentric with a long straight conductor carrying a direct current $I$. If the relative permeability $\mu_{r}$ of soft-iron is $100$, the ratio of ...

A transistor circuit is given below. The Zener diode breakdown voltage is $5.3$ V as shown. Take base to emitter voltage drop to be $0.6$ V. The value of the current gain...

A function $y(t)$, such that $y(0)=1$ and $y(1)=3e^{-1}$, is a solution of the differential equation$\dfrac{d^{2}y}{dt^{2}}+2\dfrac{dy}{dt}+y=0$. Then $y(2)$ is$5e^{-1}$$...