Electrical Machines A frog leg winding is used in a DC machine to eliminate reactance voltage produced due to communication. the use equalizer in lap winding. the use of compensating winding. the use drum winding. reactance voltage produced due to communication. the use equalizer in lap winding. the use of compensating winding. the use drum winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 4/3. 9/16. 16/9. 3/4. 4/3. 9/16. 16/9. 3/4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA 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 speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 960 RPM 970 RPM 920 RPM 940 RPM 960 RPM 970 RPM 920 RPM 940 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In an alternator the voltage generated per phase is proportional to flux per pole. All of these number of turns in coil. frequency of waveform. flux per pole. All of these number of turns in coil. frequency of waveform. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements: To control the speed of a dc shunt motor above the base speed over a reasonably wide range, the motor must 1. have compensating winding 2. have interpole winding 3. be started using a 3-point starter 4. be started using a 4-point starter Of these statements 1 and 3 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 2 and 4 are correct 1 and 3 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 2 and 4 are correct 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 = sX2. R2 = s2X2. R2 = s2X2. sR2 = X2. R2 = sX2. R2 = s2X2. R2 = s2X2. sR2 = X2. ANSWER DOWNLOAD EXAMIANS APP