Electrical Machines If terminal voltage of one 1000 rpm shunt motor is reduced to half the speed of the motor will be 500 rpm 2000 rpm 1000 rpm 250 rpm 500 rpm 2000 rpm 1000 rpm 250 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The volt-ampere euation for a long-shunt compound motor is given by Vt = Ea + Ia(ra + rs) Vt = Ea + Iara+ ILrs Vt= Ea + Iara Vt= Ea– Iara Vt = Ea + Ia(ra + rs) Vt = Ea + Iara+ ILrs Vt= Ea + Iara Vt= Ea– Iara 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 6 Ω 5.7 Ω 2.2 Ω 1.9 Ω 6 Ω 5.7 Ω 2.2 Ω 1.9 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a short circuit test on a transformer is performed at 25 V, 50 Hz, the drawn current is I1. If the test is performed by 25 V and 25 Hz and power drawn current is I2, then I1 < I2 I1 > I2 None of these I1 = I2 I1 < I2 I1 > I2 None of these I1 = I2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Conservator tank is used to act as an oil storage. to take up the expansion of oil due to temperature rise. None of these for better cooling of transformer. to act as an oil storage. to take up the expansion of oil due to temperature rise. None of these for better cooling of transformer. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the effect of armature reaction ? Armature flux weakens the main field flux. Both option B and C. Armature flux distorts the main field flux. None of the options. Armature flux weakens the main field flux. Both option B and C. Armature flux distorts the main field flux. None of the options. ANSWER DOWNLOAD EXAMIANS APP