List of top Electrical Circuits and Machines Questions

Two inductors (4 H with current \(i_1(t)=1\sin(200\pi t)\,\text{mA}\) and 5 H with \(i_2(t)=2\sin(200\pi t)\,\text{mA}\)) are mutually coupled with coupling coefficient \(k=0.6\). Currents enter the dotted ends. Find the {peak} energy stored in the coupled system (in \(\mu\)J).

The R–L circuit with $R=10\,\text{k}\Omega$ and $L=1\,\text{mH}$ is excited by a step current $I_0u(t)$. At $t=0^-$, the inductor current is $i_L=I_0/5$. The minimum time for $i_L(t)$ to reach $99%$ of its final value is _____ $\mu$s (round off to two decimal places)

In the circuit shown, \(\omega=100\pi\ \text{rad/s}\), \(R_1=R_2=2.2~\Omega\), and \(L=7~\text{mH}\). The capacitance \(C\) for which \(Y_{\text{in}}\) is purely real is _____ mF (rounded to two decimal places).

The full-scale range of the wattmeter shown is 100 W. The turns ratios are as indicated. The RMS source voltage is $V_s=200$ V. The wattmeter reading will be _____ W (rounded off to the nearest integer).

The no-load steady-state output voltage of a DC shunt generator is 200 V when it is driven in the clockwise direction at its rated speed. If the same machine is driven at the rated speed but in the opposite direction, the steady-state output voltage will be ______ V (rounded off to the nearest integer).

In the circuit shown, the Thevenin equivalent resistance $R_{\text{th}}$ across the terminals ‘a’ and ‘b’ is ______ $\Omega$ (rounded off to one decimal place).

Pair the quantities (p) to (s) with the measuring devices (i) to (iv).

Which of the following flow meters offers the lowest resistance to the flow?

Inductance of a coil is measured as $10\,\text{mH}$ using an LCR meter at $10\,\text{kHz}$, when no objects are near the coil. If a pure copper sheet is brought near the coil, the same LCR meter will read _________.

In a 3-Φ Induction motor connected to a balanced 3-Φ supply, if one of the lines suddenly gets disconnected, then the:
A. Motor will come to a standstill.
B. Motor will continue to run at the same speed with line current unchanged.
C. Motor will continue to run at a slightly reduced speed with increased line current.
D. Rotor currents will have both sf and (2-s)f components frequencies where s is slip and f is the supply frequency.
Choose the correct answer from the options given below:

Skewing is used in Induction motor in order to reduce the torque due to:

The short circuit admittance matrix of a two port network is \(\left[\begin{matrix}   0 & \frac{-1}{2} \\   \frac{1}{2} & 0  \end{matrix}\right]\). The given two port network is.

A 50 KVA 1- phase transformer has a full load efficiency of 95% at unity power factor and core loss is a 0 Watt. find the efficiency at 75% of full load and 0.8 power factor lag

if current passing through g is 0, then find \(R_X\)

Consider a unity bad back system with open loop Pole zero location given in circuit. it's R.L Cut the imaginary axis at \(s=jα (α>0)\)what is the value of \(α\).

Find dV/dt

Two Inductors are connected in series adding condition resultant is 500 MH & series opposition is 300 MH. Both inductors are equal then find coefficient of coupling?

A 3- phase squirrel cage induction motor has a starting torque of 100% of full load torque and maximum torque of 300% of full load for torque neglect stator impedances the slip at maximum torque is _____%