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

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

remains the same

increases or reduces depending upon the rotor resistance

reduces

increases

remains the same

increases or reduces depending upon the rotor resistance

reduces

ANSWER DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)
A fully controlled natural commutated 3-phase bridge rectifier is operating with a firing angle α = 30°, The peak to peak voltage ripple expressed as a ratio of the peak output dc voltage at the output of the converter bridge is

0.5

1-(√3/2)

√3-1

√3 -1

0.5

1-(√3/2)

√3-1

√3 -1

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)
A transformer designed for operation at 60 Hz supply is working at 50 Hz supply system without changing its voltage and current ratings. Compared to the full load efficiency at 60 Hz, the full load transformer efficiency at 50 Hz.

increases by 30%

remains unaltered

increases marginally

decreases marginally

increases by 30%

remains unaltered

increases marginally

decreases marginally

ANSWER DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)
Determine maximum permissible load which a 15 MVA, ONAN cooled transformer to IS : 2026 can take for 6 hr, if the initial load on it was 12 MVA. The weighted ambient temperature is 20˚C. Assume the permissible load kVA as a fraction of rated kVA is 1.25.

18.75 MVA

9.6 MVA

15 MVA

12 MVA

18.75 MVA

9.6 MVA

15 MVA

12 MVA

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)
જ્યાં ઉપમેયનો ઉલ્લેખ જ કરવામાં ન આવે અને ઉપમાન જ ઉપમેય હોય ત્યારે દ્રષ્ટાંત અલંકાર બને છે. - આ કથન સત્ય છે કે નહિ અને જો ખોટું હોય તો સત્ય કથન કયું હોઈ શકે?

ખોટું છે,જ્યાં ઉપમેયનો ઉલ્લેખ જ કરવામાં ન આવે અને ઉપમાન જ ઉપમેય હોય ત્યારે અનન્વય અલંકાર બને છે

સાચું છે.

ખોટું છે,જ્યાં ઉપમેયનો ઉલ્લેખ જ કરવામાં ન આવે અને ઉપમાન જ ઉપમેય હોય ત્યારે અતિશયોક્તિ અલંકાર બને છે

ખોટું છે,જ્યાં ઉપમેયનો ઉલ્લેખ જ કરવામાં ન આવે અને ઉપમાન જ ઉપમેય હોય ત્યારે વિરોધાભાસ અલંકાર બને છે

ખોટું છે,જ્યાં ઉપમેયનો ઉલ્લેખ જ કરવામાં ન આવે અને ઉપમાન જ ઉપમેય હોય ત્યારે અનન્વય અલંકાર બને છે

સાચું છે.

ખોટું છે,જ્યાં ઉપમેયનો ઉલ્લેખ જ કરવામાં ન આવે અને ઉપમાન જ ઉપમેય હોય ત્યારે અતિશયોક્તિ અલંકાર બને છે

ખોટું છે,જ્યાં ઉપમેયનો ઉલ્લેખ જ કરવામાં ન આવે અને ઉપમાન જ ઉપમેય હોય ત્યારે વિરોધાભાસ અલંકાર બને છે

ANSWER DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)
Two-wattmeter method is used to measure the power taken by a 3-phase induction motor on no load. The wattmeter readings are 375 W and –50 W. Calculate the reactive power taken by the load.

425/√3 VAR

325√3 VAR

325/√3 VAR

425√3 VAR

425/√3 VAR

325√3 VAR

325/√3 VAR

425√3 VAR

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 1)

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

MGVCL Exam Paper (30-07-2021 Shift 1) A fully controlled natural commutated 3-phase bridge rectifier is operating with a firing angle α = 30°, The peak to peak voltage ripple expressed as a ratio of the peak output dc voltage at the output of the converter bridge is

MGVCL Exam Paper (30-07-2021 Shift 1) A transformer designed for operation at 60 Hz supply is working at 50 Hz supply system without changing its voltage and current ratings. Compared to the full load efficiency at 60 Hz, the full load transformer efficiency at 50 Hz.

MGVCL Exam Paper (30-07-2021 Shift 1) Determine maximum permissible load which a 15 MVA, ONAN cooled transformer to IS : 2026 can take for 6 hr, if the initial load on it was 12 MVA. The weighted ambient temperature is 20˚C. Assume the permissible load kVA as a fraction of rated kVA is 1.25.

MGVCL Exam Paper (30-07-2021 Shift 1) Two-wattmeter method is used to measure the power taken by a 3-phase induction motor on no load. The wattmeter readings are 375 W and –50 W. Calculate the reactive power taken by the load.

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

MGVCL Exam Paper (30-07-2021 Shift 1)
A fully controlled natural commutated 3-phase bridge rectifier is operating with a firing angle α = 30°, The peak to peak voltage ripple expressed as a ratio of the peak output dc voltage at the output of the converter bridge is

MGVCL Exam Paper (30-07-2021 Shift 1)
A transformer designed for operation at 60 Hz supply is working at 50 Hz supply system without changing its voltage and current ratings. Compared to the full load efficiency at 60 Hz, the full load transformer efficiency at 50 Hz.

MGVCL Exam Paper (30-07-2021 Shift 1)
Determine maximum permissible load which a 15 MVA, ONAN cooled transformer to IS : 2026 can take for 6 hr, if the initial load on it was 12 MVA. The weighted ambient temperature is 20˚C. Assume the permissible load kVA as a fraction of rated kVA is 1.25.

MGVCL Exam Paper (30-07-2021 Shift 1)
Two-wattmeter method is used to measure the power taken by a 3-phase induction motor on no load. The wattmeter readings are 375 W and –50 W. Calculate the reactive power taken by the load.