1. The very peculiar advantage of corona in the circuit can be ___________
a) reduction in steepness of surge fronts
b) improvement of power factor
c) reduction in radio interference
d) reduction in steepness, radio interference and improvement of PF
Explanation: Corona reduces the surge occurring in the system.
2. When the ozone gas is produced as a by product of corona, that causes _______
a) corrosion of wires
b) reduction of power factor
c) increase of power factor
d) improvement of regulation
Explanation: Ozone gas corrodes the metals.
3. Critical voltage limit of the transmission line can be increased by ____________
a) increasing conductor’s radius
b) increasing conductor spacing
c) reducing conductor spacing
d) reducing radius of conductor
Explanation: Vα 1/r.
4. In a transmission system, the transmission parameters of distribution is/are ___________
a) resistance
b) inductance
c) capacitance and shunt conductance
d) resistance, inductance, capacitance and shunt conductance
Explanation: R, L, C, G are the distribution constants.
5. Following effects of the transmission lines
(i) Skin effect
(ii) Corona
(iii) Proximity
The effective resistance of the conductor is increased by __________
a) (i), (ii)
b) (i), (iii)
c) (ii), (iii)
d) (i), (ii), (iii)
Explanation: Effective resistance increases by skin effect, corona as well as proximity effect
6. _______ is neglected while carrying out short transmission line analysis.
a) Shunt admittance
b) Power losses
c) Series impedance
d) None of the mentioned
Explanation: Shunt admittance is neglected.
7. We transpose high voltages especially while transmitting so that the __________
a) phase voltage imbalances can be minimised
b) corona losses are reduced
c) voltage drop is minimised
d) all of the mentioned
Explanation: Transposition reduces the phase voltage imbalances by cancelling their effects.
8. While modelling a short transmission line of the overhead lines, line resistance and inductances are only considered because the line capacitance is ___________
a) zero
b) finite but small
c) finite but large
d) infinite
Explanation: Capacitance for such a distance is small and negligible.
9. For a transmission line of length not more than 80 km, then it is convenient to lump the capacitance at ________
a) receiving end
b) sending end
c) midpoint
d) anywhere long the line
Explanation: The capacitance should be best lumped at the receiving end for the simpler calculations.
10. At the no load conditions, the current is detected in the transmission line. This can be attributed due to __________
a) capacitance effect
b) proximity effect
c) corona effect
d) back flow through earth
Explanation: At the no load current the shunt connected capacitance allows the flow of the current through the circuit.