For a three-phase balanced star-connected load, if the phase voltage is 230 V, what is the line voltage?

Which semiconductor material has the widest band gap among the following?

Which test on a transformer is primarily used to determine core loss?

In a DC machine, armature reaction mainly causes:

In a buck converter operating in continuous conduction mode, the ideal output voltage is:

Which motor is preferred where high starting torque and variable speed are required?

A three-phase induction motor draws 20 A at 0.8 power factor from a 400 V supply. Its approximate active input power is:

A 10 kVA, 200/400 V transformer has a full-load secondary current of:

Which power electronic device can be turned OFF by a gate signal under normal operation?

The primary purpose of the Buchholz relay in an oil-immersed transformer is to detect:

The ripple frequency of a three-phase full-wave bridge rectifier supplied from a 50 Hz source is:

In a balanced Wheatstone bridge, the galvanometer current is:

The rotor frequency of an induction motor operating at slip s and supply frequency f is:

A CT secondary should never be open-circuited while its primary is energized because:

The primary function of a circuit breaker is to:

The condition for maximum power transfer from a DC source to a resistive load is:

Which relay is commonly used for protection of long high-voltage transmission lines?

For a symmetrical three-phase fault, the negative and zero sequence currents are:

The cogging phenomenon in an induction motor occurs mainly due to:

The Ferranti effect becomes significant in:

A common-emitter BJT amplifier provides a phase shift between input and output of approximately:

In a phase-locked loop, the VCO frequency is controlled by:

In a DC shunt motor, which condition primarily causes the motor speed to increase dangerously?

A DC series motor should never be operated without mechanical load because:

The crawling phenomenon in an induction motor is mainly associated with:

The characteristic impedance of a lossless transmission line is determined by:

The main purpose of earthing electrical equipment is to:

In an ideal voltage-source inverter, the output voltage waveform is fundamentally controlled by:

At resonance in a series RLC circuit, the impedance is:

Aliasing in an ADC occurs when the sampling frequency is:

PWM inverters are primarily used to:

The synchronous speed of a 6-pole, 50 Hz induction motor is:

Bundled conductors in EHV transmission lines are mainly used to:

The power factor of a synchronous motor can be controlled by varying its:

For an ideal op-amp operating with negative feedback, the voltage difference between its input terminals is approximately:

For a single line-to-ground fault, the positive, negative and zero sequence networks are connected:

The quality factor of a series RLC circuit at resonance is:

The reach of a distance relay is primarily determined by:

An overexcited synchronous motor operates at:

The skin effect in a conductor causes:

In a power system, the primary purpose of reactive power compensation using shunt capacitors is to:

Which logic family generally offers the lowest static power dissipation?

A 50 Hz transformer has a maximum flux of 0.01 Wb and 100 turns in its primary winding. What is the approximate RMS induced emf?

In a transformer, the maximum efficiency occurs when:

For an overhead transmission line, corona loss increases significantly with:

In a DC generator, the commutator primarily acts as:

In a synchronous generator, the frequency of generated emf is determined primarily by:

In a capacitor-input filter, increasing the capacitance generally causes the ripple voltage to:

The Barkhausen criterion for sustained oscillation requires the loop gain to satisfy:

The slip of an induction motor operating at 1440 rpm on a 50 Hz, four-pole supply is:

For an ideal boost converter operating in continuous conduction mode, the output voltage is:

In a MOSFET, the gate current under steady-state DC operation is ideally:

Which starting method provides the highest starting torque for a slip-ring induction motor?

The resolution of an ideal n-bit ADC expressed as a fraction of full-scale range is approximately:

The per-unit impedance of a transformer is independent of:

For maximum power transfer in an AC circuit, the load impedance should be: