In induction motors, the length of air gap in kept as small as mechanically possible is order to have____________?
(A) low power factor
(B) high power factor
(C) high over load capacity
(D) any of the above
Which of the following is the major consideration to evolve a good design ?
(A) Cost
(B) Durability
(C) Compliance with performance criteria as laid down in specifications
(D) All of the above
The efficiency of a machine should be as ____________ as possible to reduce the operating cost?
(A) high
(B) low
(C) either of the above
(D) none of the above
Electrical machines having power outputs ranging from a few kW up to approximately 250 kW may be classified as_____________?
(A) small size machines
(B) medium size machines
(C) large size machines
(D) any of the above
In _________ machines, the size of the shaft is decided by the critical speed which depends on the deflection of the shaft?
(A) small
(B) medium
(C) large
(D) any of the abov
The minority carrier concentration is largely a function of_____________?
(A) forward biasing voltage
(B) reverse biasing voltage
(C) temperature
(D) the amount of doping
The current due to electron flow in conduction band is the hole current in valence band?
(A) equal to
(B) less than
(C) greater than
(D) any of the above
For germanium the forbidden energy gap is_______________?
(A) 0.15 eV
(B) 0.25 eV
(C) 0.5eV
(D) 0.7eV
is an element used in semiconductors whose atoms have three valence electrons?
(A) An acceptor
(B) A donor
(C) Germanium
(D) Silicon
The carbon percentage is least in__________________?
(A) low carbon steel
(B) wrought iron
(C) cast iron
(D) malleable iron