Electrical Machines In DC machine torque depends on which of the following? speed both A and B armature current (I) flux (φ) speed both A and B armature current (I) flux (φ) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC compound motor has both shunt and series field winding. only shunt field winding. only series field winding. tertiary winding. both shunt and series field winding. only shunt field winding. only series field winding. tertiary winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of a DC machine is laminated to minimise hysteresis loss eddy-current loss temperature rise mechanical loss hysteresis loss eddy-current loss temperature rise mechanical loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 400 / 200 V, Y - Y connected wound rotor induction motor has 0.06 Ω rotor resistance and 0.3 Ω standstill reactance per phase. To make the starting torque equal to maximum torque of the motor the additional resistance required 0.24 Ω. 0.66 Ω. 0.45 Ω. 0.78 Ω. 0.24 Ω. 0.66 Ω. 0.45 Ω. 0.78 Ω. 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∝ P T∝ P² T∝ P³ T is independent of P T∝ P T∝ P² T∝ P³ ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 82.5% 67.5% 72.5% 78.5% 82.5% 67.5% 72.5% 78.5% ANSWER DOWNLOAD EXAMIANS APP