The optical fibers used for telecommunications links have dielectric constant k
ID: 1373098 • Letter: T
Question
The optical fibers used for telecommunications links have dielectric constant k = 1.6.
How long does a signal originating in California take to reach Montana in a fiber-optic cable? The distance between California and Montana is about 1400 km.
The optical fibers used for telecommunications links have dielectric constant k = 1.6. How long does a signal originating in California take to reach Montana in a fiber-optic cable? The distance between California and Montana is about 1400 km. Express your answer with the appropriate units. Delta t =Explanation / Answer
Note that the speed of light varies
v = c/sqrt(k)
As k = 1.6,
v = 2.37E8 m/s or 2.37E5 km/s
Thus,
t = d / v
= 0.00591 s or 5.91 ms [ANSWER]