MCQ
1441. Corona is affected by-
condition of atmosphere
line voltage
size & spacing of conductor
all of the above
1442. When the load factor of a power station increases, the units (kwh) generated-
are increased
remain the same
are decreased
none of these
1443. A line which connects distributor to substation is called--
service mains
distributor
feeder
infinity
1444. The surge impedance for over head line is taken as-
10-202 Ω
100-200 Ω
50-600 Ω
1000-2000Ω
1445. The common fault is overhead distribution system is-
phase to phase fault
one phase to earth fault
all phase short circuited
none of the above
1446. the minimum phase -neutral voltage at which corona occurs, is called-
critical disruptive voltage
visual critical voltage
fieash over voltage
none of the above
1447. The ring main system is used in power distribution because it--
is reliable for continuity of supply
gives better voltages regulation
results in less feeder losses
all of the above
1448. Potential difference to any equal charge is measured in,
coulomb
Ampere
joule
volt
1449. In de transmission, the skin effect is-
large
zero
small
depends on voltage
1450. At distribution substation voltage is stepped down to-
66kV
132kV
11kV
415/230 Volts
1451. Permissible variation in power frequency in Bangladesh is-
±0.1%
±1%
±5%
±10%
1452. Common declared distribution voltage in Bangladesh for low voltage circuit is-
230 Volts
250 Volts
440 Volts
380 Volts
1453. Which distribution system is more reliable?
Ring main system
Tree system
Radial System
All are equally reliable
1454. Routing means connecting-
Circuit or equipment to earth
Impent to earth
Circuit to earth
None of the above
1455. Capacitance of a transmission line is the result of-
Potential diference between the conductors
Current flow in both conductors
Current flow in either conductors
Charge per unit current
1456. Which is used for power factor improvement?
Spring motor
Sychronous motor
Commutator motor
Squirrel case motor
1457. TStability of a system is not affected by-
Reactance of line
Losses
Reactance of generator
Output torque
1458. The most severe unsymmetrical fault is-
single line-to-ground fault
line-to-line fault
double line-to-ground fault
none of the above
1459. Which of the following is not the distribution system, normally used-
3 phase 4 wire
Single phase-3 wire
Single phase -4 wire
3 phase-3 wire
1460. The highest point on the daily load curve represents-
average load
load factor
maximum load
none of the above