The intensity of a light pulse travelling along a communication channel decreases exponetially with distance x according to the relation I=I_(0)e^(-ax) where I_(0) is the intensity at x=0 and alpha is the attenuation constant. The percentage decrease in intensity after a distance of (("In"4)/(alpha)) is

The intensity of a light pulse travelling along a communication channe

1.	The intensity of a light pulse travelling along a communication channel decreases exponetially with distance x according to the relation I=I_(0)e^(-ax) where I_(0) is the intensity at x=0 and alpha is the attenuation constant. The percentage decrease in intensity after a distance of (("In"4)/(alpha)) is
Answer» 0.7 0.75 0.8 0.85 Answer :B

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