a

85.

86.

79.

001/22

The direction of rotation of a single phase induction motor can be reversed by
A) Reversing the leads of the supply

B) Reversing the leads of main winding

C) Reversing the leads of starting winding

D) Either B or ८

Which of the following can be employed for speed control of universal motors ?
ர. Resistance connected in series to armature.

i. Tappings provided on field winding.

ili. Using centrifugal device.

A) Only i and iii 8) Only ii and ‏الأ‎
‎©) Only ii 0) i, ॥ and iii
The power delivered to the load is maximum when the SCR firing angle is
A) 90° B) 180°
C) Zero D) Between 90° and 180°

~ ^ (147 has Reg = 15 K ohms, ‏و88‎ = 5 K ohms. Its intrinsic stand off ratio is
A) 0.67 B) 0.5 ©) 0.8 D) 0.33

. The operation of JFET involves

A) Recombination

B) Flow of minority carriers
C) Negative resistance

D) Flow of majority carriers

^ For half wave controlled rectifier, if firing angle is 01, then average value of output

06 voltage is given by

۷
A) Vac ‏اده‎ + 00561} 8) ४७८ 5८ = (००७०, -1)

௩
©) ४ = 0 +4 0) V, ‏لاعلا‎ cosa.)
பிது. ല്ല On :

A TRIAC is equivalent to two SCRs
A) In series B) In inverse parallel
C) In parallel D) In inverse series
Which is an example of DIAC 7
A) NTE 6408 B) OptoNCD ILR 1030
C) EddyNCD 3301 D) BT 136

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