Electrical Machines A load of 900 lbs is to be raised with a lift car weighting 855 lbs at a speed of 110 feet per minute, the over balance being 40 % and percentage efficiency 45 %. Find the horse power of the motor without counterweight 170. 180. 150. 160. 170. 180. 150. 160. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by f / s. sf. s2. sf / 2. f / s. sf. s2. sf / 2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 2, 3, 4 2, 3, 4, 5 1, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 2, 3, 4, 5 1, 3, 4, 5 1, 2, 3, 4 and 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The main disadvantage(s) of the ward-Leonard system is/are high maintenance cost. all of above. poor overall efficiency. high initial cost. high maintenance cost. all of above. poor overall efficiency. high initial cost. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the speed of a dc motor increases with load torque, then it is a comulatively compounded motor permanent magnet motor series motor differentially compounded motor comulatively compounded motor permanent magnet motor series motor differentially compounded motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ slip ring motor has double cage rotor. wound rotor. short-circuited rotor. any of the above. double cage rotor. wound rotor. short-circuited rotor. any of the above. ANSWER DOWNLOAD EXAMIANS APP
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