CIL Management Trainee Electrical Solved Papers

Which type of relay operates when the current exceeds a predetermined value?

Calculate the reactive power of the load circuit with the supply voltage of $V_s = 20\angle 0^\circ\text{ V}$.

For a uniformly charged insulating sphere of total charge $Q$ and radius $R$, which of the following statements about the electric field is correct?

During steady-state operation of a direct current (DC) chopper with constant duty ratio, what is the effect on the limit of continuous conduction mode when the switching frequency is doubled while the load parameters remain unchanged?

Choose the correct statement for the reactive power of electrodynamometer instrument (EDMI).

S1: If $Q_1$, $Q_2$ and $Q_3$ are the individual phase reactive power, then the total reactive power ($Q$) of an unbalanced system is $Q = Q_1 = Q_2 = Q_3$.

S2: In a four-wire system, unbalanced currents can flow through the neutral wire, which does not happen in a perfectly balanced system.

Find the value of the capacitor given in the following parallel circuit at the resonance condition.

What does the penalty factor in economic dispatch account for?

Let $A = \begin{bmatrix} 6 & 0 \\ 0 & 2 \end{bmatrix}$. Consider the following statements about its eigenvalues and eigenvectors:

1. Eigenvectors corresponding to distinct eigenvalues are linearly independent.
2. Any scalar multiple of an eigenvector is also an eigenvector.
3. Eigenvectors corresponding to the same eigenvalue are always orthogonal.

Which of the above statements are true?

For a buck converter,

Given:

• $f_s = 100\text{ kHz}$
• $V_{\text{in}} = 12\text{ V}$
• $V_o = 6\text{ V}$
• $I_o = 2\text{ A}$
• $L = 75\,\mu\text{H}$

Find the ripple current in the inductor.

Which of the following devices operates as a double excited system?

Two linear time-invariant systems P and Q have the following closed-loop pole locations:

System P: poles at $s = -1 \pm j2$ and $s = -5$

System Q: poles at $s = -0.2 \pm j0.5$ and $s = -3$

Which of the following statements is most accurate?

A discrete random variable $Y$ models the number of successful tests out of four independent trials, each with a probability of success $0.25$. What is the probability that $Y$ takes the value 2?

In a standard 3-phase half-controlled (3-pulse) rectifier, if the input supply frequency is $50\text{ Hz}$, the ripple frequency of the output voltage is:

A moving iron ammeter has resistance $0.1\,\Omega$ and full-scale $5\text{ A}$. To extend it to $25\text{ A}$, required shunt is:

Which of the following Excess-3 codes represents an invalid decimal digit?

The $2\%$ settling time ($T_s$) for a second-order system for damping ratio $\zeta$ and frequency is approximately given by:

The Laplace Transform of signal $r(t) = t \cdot \sin(t)$ is:

Two $10\text{-V}$ voltage sources, each with a $5\,\Omega$ series resistor, are connected in parallel. Using source transformation, find the equivalent source.

A _____ is a type of unsymmetrical fault where two of the three phases of a power system come into direct contact with each other, creating a short circuit. It does not involve the ground.

When a unit step input is applied to a unity feedback system, it has a closed-loop transfer function of the form:

If the system's peak time is measured to be $t_p = 0.65$ and the damping ratio is $\zeta = 0.5$, which of the following options is the approximate value of the natural frequency, $\omega_n$? Take the value of $\sqrt{0.75} = 0.866$ for numerical calculations.

A discrete-time LTI system has impulse response $h[n] = (0.5)^n u[n]$. Determine whether the system is stable.

Find the input power factor of the given series RLC circuit.

When a synchronous motor connected to weak grid experiences a sudden load increase, which damping phenomenon dominates first?

Two infinitely long straight line charges intersect perpendicularly at the origin:

• The first, with linear charge density $\lambda_1$, lies along the x-axis
• The second, with linear charge density $\lambda_2$, lies along the y-axis

Find the net electric field vector at the point $P(a, a, 0)$.

The transient voltage appearing across the circuit breaker contacts at the instant of arc extinction is called: