134. Pin insulators are normally used for voltage upto
A. 30 kV
B. 50 01
C. 70 kV
D. 100 kV
135. Conductors used in high voltage transmission lines are stranded to
A. make it easy to handle
B. reduce the cost
C. increase its conductivity
D. increase its tensile strength
136. Due to skin effect at high frequencies, the effective value of conductor resistance
A. decreases
B. increases
C. remains unaltered
D. may increase or decrease
137. Surge conductance in power transmission lines is due to leakage over
A. insulators
B. conductors
C. poles
D. jumpers
138. Charging current in a transmission line
A. increases the line losses
B. decreases the line losses
C. does not effect the line losses
D. none of these
139. Ground wire is used in transmission syste
A. to avoid overloading
B. to give good insulation
C. to connect a circuit conductor or other device to an earth plate
D. none of these
140. The current by alternate charging and discharging of transmission linedue to ac voltage is called
A. oscillating voltage
B. charging current
C. line current
D. discharging 'current
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