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Determine the attenuation per kilometer for a fiber whose length is 2 km, output voltage is 2.1 V at a wavelength of 0.85μm. The output voltage increases to 10.7 V when the fiber is cut-back to leave 2 metres. Determine the attenuation per km for the fiber at wavelength 0.85μm.

Determine the attenuation per kilometer for a fiber whose length is 2 km, output voltage is 2.1 V at a wavelength of 0.85μm. The output voltage increases to 10.7 V when the fiber is cut-back to leave 2 metres. Determine the attenuation per km for the fiber at wavelength 0.85μm. Correct Answer 3.5dB/km

The attenuation per kilometer can be obtained by – αdB = 10 log10(V2/V1)/(L1-L2) dB/km where L1-L2 = 1.998 and V2, V1 are output voltages.

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