GATE 1997 Electrical Engineering
40 questions across 1 session
A $$3$$-phase transformer bank consists of three identical $$2300/230$$ $$V,$$ $$15$$ $$kVA$$ single-phase transformers connected in delta/delta. The bank supplies a $$20$$ $$kVA,$...
If a diode is connected in anti - parallel with a thyristor, then
A $$5MVA$$, $$11kV$$, $$3$$-phase star connected alternator is synchronized to the bus bars and is operating with an induced $$EMF$$ of $$125\% $$ of the rated voltage. If the load...
A $$200V$$, $$10$$ $$kW$$ lap-wound $$d.c.$$ generator has $$10$$ poles and $$500$$ conductors on it's armature. If the pole face covers $$80\% $$ of the pole pitch, the pole face...
A infinitely long straight wire carries $$1000$$ $$A$$ of current and in the vicinity, there is a circular conducting loop of $$100$$ $$mm$$ diameter with the center of the loop $$...
Energy stored in a capacitor over a cycle, when excited by an $$a.c.$$ source is
In a uniform electric field, field lines and equipotentials
The capacitance of an isolated sphere of radius 10 cm in air is equal to _____ pF.
The velocity of propagation of electromagnetic wave 'n' an underground cable with relative permittivity of 3 will be ________m/sec
Express the given matrix $$A = \left[ {\matrix{ 2 & 1 & 5 \cr 4 & 8 & {13} \cr 6 & {27} & {31} \cr } } \right]$$ as a product of triangular matrices $$L$$ and $$U$$ where the diago...
A $$10$$ $$V$$ battery with an internal resistance of $$1\,\Omega $$ is connected across a nonlinear load whose $$V-1$$ characteristic is given by $$7{\rm I} = {V^2} + 2V.$$ The cu...
The use of high-speed of circuit-breakers
Determine the transfer function of the system having the following state variable representation: $$\eqalign{ & X = \left[ {\matrix{ 0 & 1 & 0 \cr 0 & 0 & 1 \cr { - 40} & { - 44} &...
Two identical coils of negligible resistance when connected in series across a $$200V,$$ $$50$$ $$Hz$$ source draws, a current of $$10$$ $$A.$$ When the terminals of one of the coi...
If an induction machine is run at above synchronous speed, it acts as
An $$SCR$$ is connected in series with a $$300V$$ $$ac$$ supply and a $$300$$ ohms load resistor calculate (a) The reading of a moving coil ammeter connected in series with the loa...
A $$5$$ $$kW,$$ $$200V$$ $$d.c.$$ shunt motor has an armature resistance of $$1$$ $$ohm$$ and shunt field resistance of $$100$$ $$ohms.$$ At no-load, the motor draws $$6A$$ from a...
For a fault at the terminals of a synchronous generator, the fault current is maximum for a
A single - phase bridge inverter is fed from a $$200V$$ $$d.c$$ supply and is operated at $$50$$ $$Hz.$$ It is connected to a load having a resistance of $$20$$ $$ohms$$ and an ind...
A major advantage of active filters is that they can be realized without using
A $$100$$ $$MVA$$, $$11$$ $$kV$$, $$3$$-phase, $$50$$ $$Hz$$, $$8$$-pole synchronous generator has an inertia constant H equal to $$4$$ $$MJ/MVA.$$ The stored energy in the rotor o...
At $$50\% $$ of full load, the armature current drawn by a $$d.c.$$ shunt motor is $$40$$ A when connected to a $$200$$ $$V$$ $$d.c.$$ mains. By decreasing the field flux, its spee...
$$\mathop {Lim}\limits_{\theta \to 0} \,{{\sin \,m\,\theta } \over \theta },$$ where $$m$$ is an integer, is one of the following :
Introduction of integral action in the forward path of a unity feedback system result in a
A synchronous motor is receiving 50% of the power it is cable to receiving from an infinite bus. If the load on the motor is suddenly reduced to 80% of the previous value, swing of...
The low voltage winding of a $$400/230V,$$ $$1$$-phase, $$50$$ $$Hz$$ transformer is to be connected to a $$25$$ $$Hz,$$ the supply voltage should be
The system represented by the transfer function $$G\left( s \right) = {{{s^2} + 10s + 24} \over {{s^4} + 6{s^3} - 39{s^2} + 19s + 84}}$$ has . . . pole $$(s)$$ in the right-half $$...
A unity feedback system with the open loop transfer function $$G\left( s \right) = {1 \over {s\left( {s + 2} \right)\left( {s + 4} \right)}}$$ has gain margin of ... $$dB.$$
A voltage $$V=400$$ sin $$314.16t$$ is applied to a $$1$$-phase transformer on no-load. If the no load current of the transformer is $$2\sin \left( {314.16t - {{85}^0}} \right),\,\...
A factory draws $$100$$ kW at $$0.7$$ p.f. lagging from a $$3$$-phase, $$11$$ kV supply. It is desired to the p.f. to $$0.95$$ lagging using series capacitors. Calculate the rating...
In a dual converter, the circulating current
In a microprocessor, the address of the next instruction to be executed, is stored in
The field coil of a two-pole $$d.c.$$ series motor is made up of two identical sections In one case $$(i)$$ of two sections of the field coil are connected in series, and in anothe...
Reactance relay is normally preferred for protection against
A single-phase alternator has a synchronous reactance of $$2$$ $$ohms$$ and negligible resistance. If it supplies $$10$$ $$A$$ to a purely capacitive load at $$200V,$$ then generat...
A potentiometer is basically
A transfer instrument employed in the standardization of a polar type $$a.c$$ potentiometer is ______
The primary current in a current transformer is dictated by
A first order system is initially at rest and excited by a step input at time $$t=0.$$ Its output becomes $$1.1$$ $$V$$ is in $$4$$ seconds and eventually reaches a steady state va...
A dynamometer type wattmeter responds to the