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. R2 = s2X2. sR2 = X2. R2 = sX2. R2 = s2X2. R2 = s2X2. sR2 = X2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines R1 is the resistance of the primary winding of the transformer. The turn ratio in terms of primary to secondary is K. Then the equivalent resistance of the primary referred to secondary is K²R1 K×R1 R1 /K R1 /K² K²R1 K×R1 R1 /K R1 /K² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, for the same value of Æ, Z and N; which one of the following statements is correct? Armature emf is more with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is less with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is more with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is less with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The overall power factor of an on load transformer is always unity. depends on the power factor of the load. is always leading. is always lagging. is always unity. depends on the power factor of the load. is always leading. is always lagging. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following motors DC excitation is not required? hysteresis motor 3-phase synchronous motor reluctance motor 3-phase synchronous generator hysteresis motor 3-phase synchronous motor reluctance motor 3-phase synchronous generator ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC machine having P no of pole pairs, Z no of conductors having length L of resistivity ρ and cross section S are arranged. what is the armature resistance for simple wave-winding ? PZL/4S PZL/ 4Sa PZL/4Sa² PZL/4Sp² PZL/4S PZL/ 4Sa PZL/4Sa² PZL/4Sp² ANSWER DOWNLOAD EXAMIANS APP