The intensity of a light pulse travelling along an optical fibre decreases exponentially with distance according to the relation l = i_(0) e^(-0.0693x) where x is in km and l_(0) is intensity of incident pulse. The intensity of pulse reduces to (1)/(4) after travelling a distance

The intensity of a light pulse travelling along an optical fibre decre

1.	The intensity of a light pulse travelling along an optical fibre decreases exponentially with distance according to the relation l = i_(0) e^(-0.0693x) where x is in km and l_(0) is intensity of incident pulse. The intensity of pulse reduces to (1)/(4) after travelling a distance
Answer» 1km 10 km 20 km 40 km Answer :C

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The intensity of a light pulse travelling along an optical fibre decreases exponentially with distance according to the relation l = i_(0) e^(-0.0693x) where x is in km and l_(0) is intensity of incident pulse. The intensity of pulse reduces to (1)/(4) after travelling a distance

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