Electrical Machine Design — Part 2 MCQs with Explanations

a D.C. potentiometer in conjunction with a volt ratio box is the correct answer to “A voltage of about 200 V can be measured”. This question is standard in competitive examination syllabi for Electrical Machine Design.

All of the above is the correct answer to “Which of the following is measured by using a vector voltmeter”. This question is standard in competitive examination syllabi for Electrical Machine Design.

Induction motor is the correct answer to “The length of air gap to be provided in ______ is primarily determined by power factor consideration.”. This question is standard in competitive examination syllabi for Electrical Machine Design.

induction type single phase energy meters is the correct answer to “Most common form of A.C. meters met with in every day domestic and industrial installations are”. This question is standard in competitive examination syllabi for Electrical Machine Design.

low is the correct answer to “Hot rolled sheets have ______ value of permeability”. This question is standard in competitive examination syllabi for Electrical Machine Design.

secondary instrument is the correct answer to “An ammeter is a”. This question is standard in competitive examination syllabi for Electrical Machine Design.

moving coil instrument is the correct answer to “An ohmmeter is a”. This question is standard in competitive examination syllabi for Electrical Machine Design.

incoming alternator is the correct answer to “In a Weston synchronoscope, the fixed coils are connected across”. This question is standard in competitive examination syllabi for Electrical Machine Design.

heating time constant is the correct answer to “The time taken by the machine to attain 0.632 of its final steady temperature rise is called”. This question is standard in competitive examination syllabi for Electrical Machine Design.

600 MW is the correct answer to “With direct water cooling it is possible to have ratings of about”. This question is standard in competitive examination syllabi for Electrical Machine Design.

high power factor is the correct answer to “In induction motors, the length of air gap in kept as small as mechanically possible is order to have”. This question is standard in competitive examination syllabi for Electrical Machine Design.

Method of average losses is the correct answer to “Which of the following methods does not take into account the maximum temperature rise under variable loadconditions”. This question is standard in competitive examination syllabi for Electrical Machine Design.

should be mounted in vertical position is the correct answer to “The switch board instruments”. This question is standard in competitive examination syllabi for Electrical Machine Design.

All of the above is the correct answer to “The heat dissipating capability of transformers of ratings higher than 30 kVA in increased by providing which of the following”. This question is standard in competitive examination syllabi for Electrical Machine Design.

winding pitch is the correct answer to “The distance between the starts of two consecutive coils measured in terms of coil sides is called”. This question is standard in competitive examination syllabi for Electrical Machine Design.

unity is the correct answer to “In a 3-phase power measurement by two wattmeter method, both the watt meters had identical readings. The power factor of the load was”. This question is standard in competitive examination syllabi for Electrical Machine Design.

electrostatic voltmeter is the correct answer to “E.m.f. of a Weston cell is accurately measured by”. This question is standard in competitive examination syllabi for Electrical Machine Design.

always 2-layer type is the correct answer to “D.C. windings are”. This question is standard in competitive examination syllabi for Electrical Machine Design.

All of the above is the correct answer to “The design of electromagnets is based upon which of the following fundamental equations”. This question is standard in competitive examination syllabi for Electrical Machine Design.

conducting and non-magnetic material is the correct answer to “The disc of an instrument using eddy current damping should be of”. This question is standard in competitive examination syllabi for Electrical Machine Design.

1.6 Wb/m2 is the correct answer to “For 275 kV transformers, using cold rolled grain oriented steel, which of the following values of flux density may be used”. This question is standard in competitive examination syllabi for Electrical Machine Design.

Direct is the correct answer to “________ cooling is the process of dissipating the armature and field winding losses to a cooling medium circulating within the winding insulation wall”. This question is standard in competitive examination syllabi for Electrical Machine Design.

a few volts only is the correct answer to “In a Schering bridge the potential of the detector above earth potential is”. This question is standard in competitive examination syllabi for Electrical Machine Design.

kWh is the correct answer to “Induction type single phase energy meters measure electric energy in”. This question is standard in competitive examination syllabi for Electrical Machine Design.

heterodoxy frequency meter is the correct answer to “To measure radio frequency, the suitable frequency meter is”. This question is standard in competitive examination syllabi for Electrical Machine Design.

maximum is the correct answer to “The cold rolled grain oriented steel has ______ permeability in the direction of the grain orientation.”. This question is standard in competitive examination syllabi for Electrical Machine Design.

at or near full load is the correct answer to “Power transformers should be designed to have maximum efficiency”. This question is standard in competitive examination syllabi for Electrical Machine Design.

Soft magnetic materials is the correct answer to “are used for construction of core of electromagnets.”. This question is standard in competitive examination syllabi for Electrical Machine Design.

Schering bridge is the correct answer to “For measurements on high voltage capacitors, the suitable bridge is”. This question is standard in competitive examination syllabi for Electrical Machine Design.

by eliminating the control springs is the correct answer to “A moving-coil permanent-magnet instrument can be used as flux meter”. This question is standard in competitive examination syllabi for Electrical Machine Design.

large is the correct answer to “In ______ machines, the size of the shaft is decided by the critical speed which depends on the deflection of the shaft.”. This question is standard in competitive examination syllabi for Electrical Machine Design.

Cast-iron is the correct answer to “is usually used for brush rockers”. This question is standard in competitive examination syllabi for Electrical Machine Design.

2000 to 2500 r.p.m. is the correct answer to “Commercial available medium size machines have a speed range of ______ .”. This question is standard in competitive examination syllabi for Electrical Machine Design.

1.1 to 1.35 Wb/m2 is the correct answer to “The usual values of maximum flux densities for distribution transformers using hot rolled silicon steel are”. This question is standard in competitive examination syllabi for Electrical Machine Design.

permanent magnet D.C. generator is the correct answer to “The electrical power to a meggar is provided by”. This question is standard in competitive examination syllabi for Electrical Machine Design.

large in comparison with the armature mmf is the correct answer to “In D.C. machines, ir order to prevent excessive distortion of field form by the armature reaction, the field mmf must be made”. This question is standard in competitive examination syllabi for Electrical Machine Design.

all of the above is the correct answer to “Various adjustments in an energy meter include”. This question is standard in competitive examination syllabi for Electrical Machine Design.

2.2 to 3.2 A/mm2 is the correct answer to “For large power transformers, self oil cooled type or air blast type which of the following values of current density may be used”. This question is standard in competitive examination syllabi for Electrical Machine Design.

frequency error is the correct answer to “The rectifier instrument is not free from”. This question is standard in competitive examination syllabi for Electrical Machine Design.

both (A) and (B) is the correct answer to “Instrument transformers are”. This question is standard in competitive examination syllabi for Electrical Machine Design.