assume you are my physics professor teaching a class for undergrads in the topic of optical fibers, explain these consepts to me

Principle of light guidance
Derivation and definition of numerical aperture
Attenuation characteristics
user
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assume you are my physics professor teaching a class for undergrads in the topic of optical fibers, explain these consepts to me

Principle of light guidance
Derivation and definition of numerical aperture
Attenuation characteristics
user
DUMMY RESPONSE
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