List of top Electrical Engineering Questions asked in Telangana State Post Graduate Engineering Common Entrance Test

Speed of 3-$\phi$ synchronous motor can be controlled by varying frequency at constant torque at
If voltage of a d.c. servo-motor increases, then the Torque-speed characteristic and slope respectively are
The step angle of a stepper motor is given by
On two sides of a 3-\(\phi\) star / delta transformer the
The input of a 98% efficiency, 2000 rpm separately excited dc motor is 5 kW. The torque output is
The speed of a d.c. series motor at an armature current of 10 A is 800 rpm. If load torque is proportional to square of speed, then at 5 A the speed will be
If \( R_1, R_2, R_3, R_4, R_5 \) are resistances of each of five sections of starter of d.c. shunt motor, then these resistances are
Dummy coils are used in wave wound d.c. machines to reduce
Choose a wrong choice on d.c. machine regarding compoles or compensating winding
Swinburne’s test measures the following on a 200 V, 15 kW dc shunt motor:
Input current = 7 A; Field current = 2 A. Estimate field copper loss and iron \& frictional losses. Assume \( R_a = 0.04 \Omega \)
The current and power factor of a 3–\(\phi\) induction motor at no-load are respectively
A 3-\(\phi\), 400 V, 50 Hz, 4 pole induction motor has rotor resistance and standstill reactance of 0.08 Ω and 0.4 Ω respectively. What is its approximate speed at maximum torque?
The external rotor resistance of a 3-\(\phi\) induction motor is increased more than the resistance required to get maximum starting torque. Then maximum torque occurs in \underline{\hspace{2cm} of Torque (y-axis) – Speed (x-axis) characteristic plot.
A 1-\(\phi\), 230 V, 50 Hz transformer is operated at 230 V, 60 Hz. Then its
Indicate a correct choice on currents during open circuit (OC) and short circuit (SC) tests of transformer
A 11kV/3.3kV, 100 MVA, 3-phase transformer has equivalent impedance seen from LV side of (1.2 + j4.8) Ω. The per unit impedance of the transformer is
If R and X are equivalent resistance and equivalent reactance of a transformer respectively, then at maximum voltage regulation, the power factor is
Magnetic dipole moment is ______ of the loop, its direction is normal to the loop
\( \nabla \cdot \vec{B} = 0 \), shows that
The reciprocal of reluctance is
The magnetization \( M \), in amperes per meter is
The slip-speed of a 3-\(\phi\), cage, 50 Hz, induction motor is 20 rpm at no-load. If slip-speed is doubled due to load, then the electrical equivalent of mechanical load will
The time period of rotor current of a 3-\(\phi\), 4-pole, 50 Hz, induction motor is 200 ms. Then slip speed of the motor is
Two identical coaxial circular coils carry the same current 1 amp but in opposite directions. The magnitude of the magnetic field \( B \) at a point on the axis midway between the coils is
Choose the correct statement of Reciprocity theorem in single source network: