Electrical Machines Armature reaction in a DC machine is in direct opposition to the main poles. is in the same direction as the main poles. makes an angle of 90° with the main pole axis. makes an angle with the main pole axis which is load dependent. is in direct opposition to the main poles. is in the same direction as the main poles. makes an angle of 90° with the main pole axis. makes an angle with the main pole axis which is load dependent. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC generator rotates at 1500 rpm. How many times in a second, will the emf induced in each armature conductor changes its direction? 100. 200. 750. 500. 100. 200. 750. 500. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of double squirrel cage winding on the rotor provides reduced starting torque. higher efficiency. a large starting torque. low noise. reduced starting torque. higher efficiency. a large starting torque. low noise. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines which of the following losses are negligible in blocked rotor test? iron loss mechanical loss copper loss both A and B iron loss mechanical loss copper loss both A and B ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The magnetic field which initially induces emf in the armature in a self excited DC generator is because of residual magnetism. permanent magnets. None of these armature reaction. residual magnetism. permanent magnets. None of these armature reaction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor is running with a divertor connected across its field winding. If the divertor resistance is reduced then the speed of the motor will decrease. increase. become execessively high. remain unaltered. decrease. increase. become execessively high. remain unaltered. ANSWER DOWNLOAD EXAMIANS APP
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