Electrical Machines The speed regulation of a DC motor is given as NnL − NfL. (NnL − NfL)/NfL. NnL/NfL. (NfL − NnL)/NnL. NnL − NfL. (NnL − NfL)/NfL. NnL/NfL. (NfL − NnL)/NnL. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A compound dc generator is delivering full load current at a terminal voltage of 230 V. Its series-field winding gets short circuited. If its terminal voltage 1. becomes more than 230 V, it is overcompounded generator 2. becomes more than 230 V, it is differentially compounded generator 3. becomes less than 230 V, it is overcompounded generator 4. becomes less than 230 V, it is differentially compounded generator 5. becomes less than 230 V, it is level compounded generator From these, the correct answer is 1, 4, 5 2, 3, 5 1, 4 2,3 1, 4, 5 2, 3, 5 1, 4 2,3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC series motor is best suited for electric traction as It consume less power. It runs at very high speed at light load. It is cheaper in cost. It develops high starting torque. It consume less power. It runs at very high speed at light load. It is cheaper in cost. It develops high starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC motor under constant terminal voltage what is the relation between torque (Te) and power (P) T is independent of P T∝ P³ T∝ P T∝ P² T is independent of P T∝ P³ T∝ P T∝ P² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The change in speed of a DC generator due to increased load is corrected by increasing terminal voltage. increasing armature resistance. increasing armature cooling. increasing input power of the prime mover. increasing terminal voltage. increasing armature resistance. increasing armature cooling. increasing input power of the prime mover. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected there was no residual magnetism in the field circuit field resistance was higher than critical resistance there was a break in the armature circuit field winding was wrongly connected there was no residual magnetism in the field circuit ANSWER DOWNLOAD EXAMIANS APP