Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes twice the initial value 1/2 of the initial value 4 time the initial value 1/4 of the intial value twice the initial value 1/2 of the initial value 4 time the initial value 1/4 of the intial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to reactance voltage. armature reaction. high resistance of carbon brushes. presence of commutator. reactance voltage. armature reaction. high resistance of carbon brushes. presence of commutator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC Shunt Motor has disadvantage(s) of not suitable for rapidly changing loads. constant speed. less expensive. none of above. not suitable for rapidly changing loads. constant speed. less expensive. none of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 0 Hz 25 Hz 50 Hz 100 Hz 0 Hz 25 Hz 50 Hz 100 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In double cage induction motor, the inner cage offers high resistance and high reactance. low resistance and low reactance. high resistance and low reactance. low resistance and high reactance. high resistance and high reactance. low resistance and low reactance. high resistance and low reactance. low resistance and high reactance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 2, 5 1, 3, 5 1, 4, 6 1, 2, 6 1, 2, 5 1, 3, 5 1, 4, 6 1, 2, 6 ANSWER DOWNLOAD EXAMIANS APP
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