5. The ends of a 10 cm laser rod, index of refraction = 1.76, has its ends coated for reflectivity of 99.9 % and 90 %. If there is no excited state absorption (  calculate a) the fractional loss per pass and b) the decay time of the cavity

the fractional loss per pass =0.053

the decay time of the cavity =11 ns

Explanation:

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the fractional loss per pass=

but no excited state absorption, therefore is 0

=0.053

b) the decay time of the cavity:

=1.1 *10^-8 seconds

=11 ns

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there are no correct statementd on the list of choices you provided.