52.

53.

54.

85.

86.

57.

൫8.

60.

The direction of rotation of a DC motor is determined by :

(^) Fleming's right hand rule (18 Fleming's left hand rule

(C) Right hand grip rule (10) Maxwell's cork screw rule
The back e.m.f. of a D.C motor depends on :

(ಗಿ) Shape of conductors (B) Field flux

(0) Type of commutator (D) Brush material

The main function of starter of the DC Motor is to :
(A) Limit the starting current (ए) Limit the back e.m.f.
(C) Increase the field circuit resistance (D) Decrease armature resistance

The speed of DC shunt motor has to be controlled through the field, the most suitable starter
for this purpose is :

(ക D.O.L starter (B) 2 point starter

(C) 3 point starter (D) 4 point starter

The speed of a DC motor is :
(ക) Directly proportional to the back e.m.f. and inversely proportional to the flux
(B) Inversely proportional to back e.m.f and directly proportional to flux
(C) Directly proportional to the e.m.f as well as the flux
(D) Directly proportional to current

Insulation resistance is measured in :

(ಯಿ) Mega watts (B) Kilo ohms
(C) Mega chms (D) Kilo volts
The running speed of a 3 phase squirrel cage induction motor is :
(A) Synchronous speed (B) More than synchronous speed
(C) Double synchronous speed (D) Less than synchronous speed

For 3 HP, 3phase 415V, 50 Hz squirrel cage induction motor started through a D.0.L starter,
the back up fuse rating will be :

(5) 15 Amps (B) 10 Amps
(0 6 4778 (D) 4Amps

When remote ‘ON’ and OFF are used in a D.O.L starter, the remote ‘ON’ button should be
connected with the existing ‘ON’ button in :

(A) Series (18) Series and parallel

(0 Bridge circuit (D) Parallel

9 101/2016
[7.7.೧.]