MGVCL Exam Paper (30-07-2021 Shift 1) Calculate the capacitance per meter of a 50 Ω load cable that has an inductance of 50 nH/m. 10 pF 20 pF 30 pF 40 pF 10 pF 20 pF 30 pF 40 pF ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Z = √(L/C)C = L/Z²C = 50*10⁻⁹/(50*50)C = 0.02 nFC = 20 pF
MGVCL Exam Paper (30-07-2021 Shift 1) In Microsoft Word, which of the following menu is used to add Headings that are displayed automatically in the top margin of all pages? View Menu Tools Menu Insert Menu Format Menu View Menu Tools Menu Insert Menu Format Menu ANSWER DOWNLOAD EXAMIANS APP
MGVCL Exam Paper (30-07-2021 Shift 1) A coil having an inductance of 100 mH is magnetically coupled to another coil having an inductance of 900 mH. The coefficient of coupling between the coils is 0.45. Calculate the equivalent inductance if the two coils are connected in series aiding. 932 mH 1135 mH 1270 mH 730 mH 932 mH 1135 mH 1270 mH 730 mH ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Mutual inductance (M) = k*√(L1*L2)k = 0.45M = 0.45*√(900*100*10⁻⁶) = 135 mHLeq = L1 + L2 + 2MLeq = 900 + 100 + 270Leq = 1270 mH
MGVCL Exam Paper (30-07-2021 Shift 1) If a 415 V, 50 Hz, star-connected, three-phase squirrel-cage induction motor is operated from a 415 V, 70 Hz supply, the torque that the motor can now provide while drawing rated current from the supply increases or reduces depending upon the rotor resistance reduces increases remains the same increases or reduces depending upon the rotor resistance reduces increases remains the same ANSWER DOWNLOAD EXAMIANS APP
MGVCL Exam Paper (30-07-2021 Shift 1) Murray loop test is performed on a faulty cable 300 m long. At balance, the resistance connected to the faulty core was set at 15 Ω and the resistance of the resistor connected to the sound core was 45 Ω. Calculate the distance of the fault point from the test end. 450 m 225 m 150 m 75 m 450 m 225 m 150 m 75 m ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Where,R2 is the resistance connected to the faulty core in ohmR2 is the resistance of the resistor connected to the sound core in ohmR1 Distance of fault location (Lx) = R2/(R1 + R2)*(2*L)= (15/60)*600= 150 m
MGVCL Exam Paper (30-07-2021 Shift 1) For protection of inter-turn fault in transformer, the relays preferred are Buchholz's relay, overcurrent relay and differential relay Overcurrent relay and Buchholz's relay Buchholz's relay and differential relay Overcurrent relay and differential relay Buchholz's relay, overcurrent relay and differential relay Overcurrent relay and Buchholz's relay Buchholz's relay and differential relay Overcurrent relay and differential relay ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Intern turn winding fault can be easily detect by differential protection relay.Also detect by buchholz relay (gas operated relay), cause buchholz relay is used to detect the internal fault of transformer.