Electrical Machines which of the following losses are negligible in blocked rotor test? copper loss both A and B iron loss mechanical loss copper loss both A and B iron loss mechanical loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3-phase induction motor, if the supply voltage and frequency are reduced by the same ratio, then slip at which maximum torque occurs is more and maximum torque decreases less and maximum torque decreases more and maximum torque remains constant less and maximum torque increases more and maximum torque decreases less and maximum torque decreases more and maximum torque remains constant less and maximum torque increases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The compensating winding in a DC machine is located in armature slots for compensation of the armature reaction. is located on pole shoes for avoiding the flashover at the commutator. is located on commutating poles for improving commutation. is located on pole shoes to avoid the sparking at the brushes. is located in armature slots for compensation of the armature reaction. is located on pole shoes for avoiding the flashover at the commutator. is located on commutating poles for improving commutation. is located on pole shoes to avoid the sparking at the brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V DC series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 ohms. The value of resistance which must be added to obtain rated torque at 1000 rpm is 6 ohms. 2.2 ohms. 1.9 ohms. 5.7 ohms. 6 ohms. 2.2 ohms. 1.9 ohms. 5.7 ohms. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and the flux of a DC motor are held constant and voltage applied across its armature is increased by 5%, the speed of the motor will reduce by 5 %. remain unchanged. depend on other factors. increase by 5 %. reduce by 5 %. remain unchanged. depend on other factors. increase by 5 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, the angle between the stator and rotor fields is 90o. 0o. dependent upon the load. 180o. 90o. 0o. dependent upon the load. 180o. ANSWER DOWNLOAD EXAMIANS APP