Electrical Engineering GATE 2025 Questions with Answer

Ques 14 Electrical Machines

A 3-phase, 400 V, 4 pole, 50 Hz star connected induction motor has the following parameters referred to the stator: R_r'=1Ω, X_s=X_r'=2Ω
Stator resistance, magnetizing reactance and core loss of the motor are neglected. The motor is run with constant V/f control from a drive. For maximum starting torque, the voltage and frequency output, respectively, from the drive, is closest to,

Ques 15 Electrical Machines

The operating region of the developed torque (T_em) and speed (ω) of an induction motor drive is given by the shaded region OQRE in the figure. The load torque (T_L) characteristic is also shown. The motor drive moves from the initial operating point O to the final operating point S. Which one of the following trajectories will take the shortest time?

Ques 16 Electrical Machines

The induced emf in a 3.3 kV, 4 pole, 3-phase star connected synchronous motor is considered to be equal and in phase with the terminal voltage under no load condition. On application of a mechanical load, the induced emf phasor is deflected by an angle of 2° mechanical with respect to the terminal voltage phasor. If the synchronous reactance is 2 Ω, and stator resistance is negligible, then the motor armature current magnitude, in ampere, during loaded condition is closest to, ______ (round off to two decimal places).

Ques 17 Electrical Machines

The transformer connection given in the figure is part of a balanced 3-phase circuit where the phase sequence is "abc". The primary to secondary turns ratio is 2:1. If (I_a+I_b+I_c=0) then the relationship between I_A and I_ad will be

Ques 18 Electromagnetics

An air filled cylindrical capacitor (capacitance C₀) of length L, with a and b as its inner and outer radii, respectively, consists of two coaxial conducting surfaces. Its cross-sectional view is shown in Fig. (i). In order to increase the capacitance, a dielectric material of relative permittivity ε_r is inserted inside 50% of the annular region as shown in Fig. (ii). The value of ε_r for which the capacitance of the capacitor in Fig. (ii), becomes 5C₀ is

Ques 19 Electromagnetics

Let a_R be the unit radial vector in the spherical co-ordinate system. For which of the following value(s) of n, the divergence of the radial vector field f(R)=a_R(1/Rⁿ) is independent of R?

Ques 20 Electromagnetics

Given F=a_x(3y+k₁z)+a_y(k₂x-2z)+a_z(k₃y-x), where a_x, a_y and a_z are the unit vectors in Cartesian coordinate system.
The product k₁k₂k₃ for which F is irrotational is ______ (round off to nearest integer).

Ques 21 Electromagnetics

Which one of the following figures represents the radial electric field distribution E_R caused by a spherical cloud of electrons with a volume charge density, ρ=-3ρ₀ for 0≤R≤a (both ρ₀, a are positive and R is the radial distance) and ρ=0 for R>a?

Ques 22 Electronic Devices

The op-amps in the following circuit are ideal. The voltage gain of the circuit is ______ (round off to the nearest integer).

Ques 23 Electronic Devices

In the Wheatstone bridge shown below, the sensitivity of the bridge in terms of change in balancing voltage E for unit change in the resistance R, in mV/Ω, is ______ (round off to two decimal places).

Ques 24 Electronic Devices

In the circuit, both Q₁ and Q₂ have a current gain of 100 and V_BE=0.7 V. The small signal voltage gain is ______ (round off to two decimal places).

Ques 25 Electronic Devices

In the Wheatstone bridge shown below, the sensitivity of the bridge in terms of change in balancing voltage E for unit change in the resistance R, in mV/Ω, is ______ (rounded off to two decimal places).

Ques 26 Electronic Devices

Which one of the following statements is true about the small signal voltage gain of a MOSFET based single stage amplifier?