56. If the power factor of the load decreases, the transmission line losses are :
(A) increased
(B) decreased by two times
(C) decreased by 1.5 times
(D) constant
57. A d.c. motor takes a large value of current at the time of starting due to :
(A) high armature resistance
(B) weak shunt field
(C) armature reaction
(D) absence of back e.m.f.
58. A zener diode normally operates at :
(A) forward bias providing constant voltage
(B) forward bias providing constant current
(C) reverse bias providing constant voltage
(D) reverse bias providing constant current
59. If the specific gravity of electrolyte (H2SO4) in a lead acid cell increases, the internal resistance of the cell :
(A) remains unchanged
(B) is increased
(C) is decreased
(D) is equal to load resistance
60. In a NPN type Bi-polar junction transistor :
(A) Emitter current + Base current=0
(B) Base current=Emitter current +Collector current
(C). Collector current= Base current + Emitter current
(D) Emitter current=Base current +Collector current