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81.

The power factor of a 3 phase induction motor near full load is expected to be around

A.	0.8 leading	B.	0.8 lagging
C.	0.5 lagging	D.	0.5 leading
E.	0.1 lagging

82.

The power factor of a 3 phase induction motor will be least

A.	at full load	B.	at 80% load
C.	at 5% load	D.	at 25% load
E.	at no load

83.

When the reactive component is small

A.	the phase angle will be small and p.f. will be unity	B.	the phase angle will be small and p.f. will be leading
C.	the phase angle will be small and p.f. will be high	D.	the phase angle will be large and p.f. will be low
E.	the phase angle will be large and p.f. will be high

84.

The power factor of a three phase induction motor at no load will be

A.	Zero	B.	0.2 to 0.3 lagging
C.	0.2 to 0.3 leading	D.	0.5 to 0.6 leading
E.	0.5 to 0.6 lagging

85.

Which of the following motor can operate on lagging as well as leading power factor?

A.	Universal motor	B.	Squirrel cage induction motor
C.	Synchronous motor	D.	Reluctance motor
E.	Capacitor run motor

86.

Which of the following equipment can be used for improving the power factor ?

A.	Static capacitors	B.	Synchronous condenser
C.	Phase advancer	D.	Any of the above
E.	None of the above

87.

Which of the following is an advantage of using static capacitors of power factor improvement?

A.	Low losses within the capacitors	B.	No rotating parts
C.	Can be easily installed	D.	Can work under normal atmospheric conditions
E.	All of the above

88.

The useful life of static capacitor can be expected to be

A.	2 to 3 months	B.	6 to 8 months
C.	1 to 2 years	D.	8 to 10 years
E.	50 to 100 years

89.

Phase, advancers for power factor improvement are generally used for

A.	Induction motors below 10 HP	B.	Induction motors below 100 HP
C.	Induction motors below 200 HP	D.	Are lamps of high wattage
E.	Transformers of 100 MVA and above

90.

A 3 phase 15 kW induction motor has a p.f. of 0.75 lagging. A bank of capacitor is connected in delta across the supply terminals and p.f. raised to 0.9 lagging. The KVAR rating of the capacitors connected in each phase will be nearly

A.	1	B.	2
C.	4	D.	20
E.	250