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 In a 3-phase induction motor, torque and supply voltage are related as T ∝ 1/V T∝ V² T ∝ V T ∝ 1/V² T ∝ 1/V T∝ V² T ∝ V T ∝ 1/V² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by the a 230 V DC motor of armature resistance 0.5 Ω and back emf 200 V is 40 660 600 60 40 660 600 60 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 lap-winding ? PZL/4SP² PZL/4S PZL/ 4Sa PZL/4Sa² PZL/4SP² PZL/4S PZL/ 4Sa PZL/4Sa² ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3 ,5 2, 3, 4 2, 3, 4, 5 1, 2, 3 2, 3 ,5 2, 3, 4 2, 3, 4, 5 1, 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What does the use the of height flux density value in transformer design lead to? Increase in weight/KVA. Reduced copper loss. Decrease in weight/KVA. Reduced iron loss. Increase in weight/KVA. Reduced copper loss. Decrease in weight/KVA. Reduced iron loss. ANSWER DOWNLOAD EXAMIANS APP