CL wadhwa bits solutions (101-105)

Lesson 17 of 21 • 38 upvotes • 14:49mins

Anvesh Sameer

101. The corona loss on a particular system at 50 Hz is 1 kW/phase per km. The corona loss on the same system with supply frequency 25 Hz will be: (a) 1 kW/phase/km (b) 0.5 kW/phase/km (c) 0.667 kw/phase/km (d) None of the above. 102. A system is said to be effectively grounded if its: (a) Neutral is grounded directly (b) Ratio of X X 0 1 > 3.0 (c) Ratio of R X 0 1 > 2.0 (d) Ratio of X X 0 1 < 3.0. 103. For effective application of counterpoise is should be buried into the ground to a depth of: (a) 1 metre (b) 2 metres (c) Just enough to avoid theft (d) None of the above. 104. If r is the radius of the conductor and R the radius of the sheath of the cable, the cable operates stably from the view point of dielectric strength if: (a) r R > 1.0 (b) r R < 1.0 (c) r R < 0.632 (d) r R < 0.368. 105. Three insulating materials with same maximum working stress and permittivities 2.5, 3.0, 4.0 are used in a single core cable. The location of the materials with respect to the core of the cable will be: (a) 2.5, 3.0, 4.0 (b) 3.0, 2.5, 4.0 (c) 4.0, 3.0, 2.5 (d) 4.0, 2.5, 3.0.