Electrical Machines Which of the following methods are used to control the speed of DC motors is field current control supply voltage control All of these armature circuit resistance control field current control supply voltage control All of these armature circuit resistance control ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Shunt Motor if the load current increases keeping the terminal voltage constant, then flux will increase. decrease. remain constant. any of the above. increase. decrease. remain constant. any of the above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Remain unaltered. Oscillate around the normal speed. Increase. Reduce. Remain unaltered. Oscillate around the normal speed. Increase. Reduce. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When R2 is rotor resistance, X2 the rotor reactance at supply frequency and s the slip, then the condition for maximum torque under running condition will be R2 = s2X2. R2 = s2X2. R2 = sX2. sR2 = X2. R2 = s2X2. R2 = s2X2. R2 = sX2. sR2 = X2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the back emf in DC motor vanishes suddenly the motor will run at very high speed. burn. run at very low speed. start haunting. run at very high speed. burn. run at very low speed. start haunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Stray losses in transformer occurs in steel core. transformer insulating oil. paper insulation in transformers. winding conductors and steel structures of transformer. steel core. transformer insulating oil. paper insulation in transformers. winding conductors and steel structures of transformer. ANSWER DOWNLOAD EXAMIANS APP