ECET EEE 2012-4

1. Due to the ferranti effect on long overhead lines

A. receiving end voltage is less than the sending end voltage
B. receiving end voltage is more than the sending end voltage
C. receiving end voltage is equal to sending voltage
D. receiving end voltage is not effected

Answer : B. receiving end voltage is more than the sending end voltage
Explanation:-

2. Corona occurs between two transmission lines when they are

A. Closely spaced
B. Widely spaced
C. having high potential difference
D. carrying DC Power

Answer : C. having high potential difference
Explanation:-

3. Surge impedance of a transmission line is given by

A. sqrt(L/C)
B. sqrt(C/L)
C. sqrt(LC)
D. 1/sqrt(LC)

Answer : A. sqrt(L/C)
Explanation:-

4. The general distance for short transmission line is given by

A. less than 80km
B. 80km-250km
C. more than 250km
D. 150km - 300km

Answer : A. less than 80km
Explanation:-

5. The resistance of the line

A. increase with increase in frequency
B. decreases with increase in frequency
C. is independant of frequency
D. increases with decrease in frequency

Answer : C. is independant of frequency
Explanation:-

6. In HVDC transmission system AC is converted to DC using

A. Rectifier
B. Inverter
C. Chopper
D. Cycloconverter

Answer : A. Rectifier
Explanation:-

7. Suspension type insulators are used for voltages beyond

A. 220v
B. 400v
C. 11kv
D. 33kv

Answer : D. 33kv
Explanation:-

8. Power factor of inductrial load is generally

A. unity
B. leading
C. lagging
D. zero

Answer : C. lagging
Explanation:-

9. Pole mounted transformer stations are meant for

A. primary transmission
B. primary distribution
C. secondary transmission
D. secondary distribution

Answer : D. secondary distribution
Explanation:-

10. Transmission lines are transposed to

A. reduce copper loss
B. reduce skin effect
C. prevent interference with communication lines
D. present short circuit between conductors

Answer : C. prevent interference with communication lines
Explanation:-