Electrical Machines An inverted V curve of synchronous motor shows variation of supply voltage and field current at constant excitation. power factor and supply voltage during hunting. supply voltage and excitation current at constant load. power factor and DC excitation at constant load. supply voltage and field current at constant excitation. power factor and supply voltage during hunting. supply voltage and excitation current at constant load. power factor and DC excitation at constant load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines It is an advisable to use auto transformer if the transformation ratio is 0.25. near to 1. Greater than 1. 0.5. 0.25. near to 1. Greater than 1. 0.5. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V dc series motor takes 40 A when giving its rated output at 1500 rpm. Its resistance is 0.3 Ω. The value of resistance which must be added to obtain rated torque at 1000 rpm is 2.2 Ω 1.9 Ω 6 Ω 5.7 Ω 2.2 Ω 1.9 Ω 6 Ω 5.7 Ω 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 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 1 and 3 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a seperately excited DC Motor if field current is increased, it will Reduce armature heating. Reduce starting torque. Increase acceleration duration. Increase speed Reduce armature heating. Reduce starting torque. Increase acceleration duration. Increase speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the eddy current loss if the supply frequency of a transformer becomes double? Four times. Remains same. Doubled. Eight times. Four times. Remains same. Doubled. Eight times. ANSWER DOWNLOAD EXAMIANS APP