Question

3. The thickness of a paper is 10-4 m. Find the number of papers in 1 metre.
4. What is the distance in km of a star from the earth from which light takes 10 years to reach us?
Fama
104
fans Distance = 9.4​

Answer 1

Explanation:

t=12×10

−7

m,λ=6×10

−7

m,n=1,μ=?

The shifts,

(μ−1)t=nλ

μ=

t

nλ

+1=

12×10

−7

1×6×10

−7

+1=1.5

The refractive index of mica = 1.5