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A cable of core radius 1.25cm and impregnated paper insulation of thickness 2.13cm and relative permittivity 3.5. Compute the capacitance of the cable/km(in nF)

A cable of core radius 1.25cm and impregnated paper insulation of thickness 2.13cm and relative permittivity 3.5. Compute the capacitance of the cable/km(in nF) Correct Answer 195.7

Capacitance between coaxial cylinders of inner radius 1.25cm and outer radius 1.25 + 2.13 = 3.38cm will be C = 2πεL/ ln(b/a). Put b = 3.38, a = 1.25 and L = 1000m, we get C = 1.957 x 10-7 = 195.7 nF.

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S1: Instantly the full load yanked Gordy towards the side of the bridge.
P: But the pull of the cable was too much.
Q: He could hardly feel the cable, slipping through his fingers, ripping off his gloves, and streaking over the railing like an escaping snake.
R: It smashed his hands hard against the top of the railing, causing a split - second feeling of fierce pain followed by numbness.
S: He held on to the cable; it had been hard work lifting it, and he did not want to have to start over again.
S6: Feeling a sharp burning sensation where the cable was speeding between his things, Gordy rose on tiptoe and as he did, the slithering coil of cable tightened around his left foot and yanked him over the railing.

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