Answer:
a) [tex]1.517\times10^{-11}[/tex] s
b) 3.41 mm
Explanation:
a)
We take the speed of light, c = [tex]3.0\times10^8[/tex] m/s and the refractive index of glass as 1.517.
Speed = distance/time
Time = distance/speed
Refractive index, n = speed of light in vacuum / speed of light in medium
[tex]n=\dfrac{c}{s}[/tex]
[tex]s=\dfrac{c}{n}[/tex]
[tex]t=\dfrac{d}{c/n}[/tex]
[tex]t=\dfrac{dn}{c}[/tex]
[tex]t=\dfrac{3\times10^{-3}\times1.517}{3.0\times10^8}[/tex]
[tex]t=1.517\times10^{-11}[/tex]
b)
We take the refractive index of water as 1.333.
Speed in water = speed in vacuum / refractive index of water
Distance = speed * time
[tex]d=s\times t[/tex]
[tex]d=\dfrac{c}{n_w}\times \dfrac{3\times10^{-3}\times1.517}{c}[/tex]
[tex]d=\dfrac{3\times10^{-3}\times 1.517}{1.333}[/tex]
d = 3.41 mm
