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 = sX2. R2 = s2X2. sR2 = X2. R2 = s2X2. R2 = sX2. R2 = s2X2. sR2 = X2. R2 = s2X2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the field system has to be provided on stator unlike synchronous machines Where in it could be on any member, because dc machines are comparatively low rating machines. commutator action is not possible otherwise it reduces field structure iron losses it gives more uniform air-gap flux distribution dc machines are comparatively low rating machines. commutator action is not possible otherwise it reduces field structure iron losses it gives more uniform air-gap flux distribution ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3-phase induction motor, if the supply voltage and frequency are reduced by the same ratio, then slip at which maximum torque occurs is more and maximum torque decreases less and maximum torque decreases more and maximum torque remains constant less and maximum torque increases more and maximum torque decreases less and maximum torque decreases more and maximum torque remains constant less and maximum torque increases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum power developed by a synchronous motor depends on excitation and load angle supply voltage and load angle supply voltage, load angle and excitation supply voltage and excitation excitation and load angle supply voltage and load angle supply voltage, load angle and excitation supply voltage and excitation ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine the armature mmf is rotating with respect to field poles. stationary with respect to armature. stationary with respect to field poles. rotating with respect to field poles as well as armature. rotating with respect to field poles. stationary with respect to armature. stationary with respect to field poles. rotating with respect to field poles as well as armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a step down transformer which one of the following statements is true? Secondary power is less than primary power. Secondary current is less than primary current. Number of secondary turns is more than that of primary. Number of secondary turns is less than primary turns. Secondary power is less than primary power. Secondary current is less than primary current. Number of secondary turns is more than that of primary. Number of secondary turns is less than primary turns. ANSWER DOWNLOAD EXAMIANS APP