All Problems

Photometry and Geometrical Optics

Problem 5.63

Find the curvature radius of a ray of light propagating in a horizontal direction close to the Earth's surface where the gradient of the refractive index in air is equal to approximately \(3 \cdot 10^{-8} \mathrm{~m}^{-1} .\) At what value of that gradient would the ray of light propagate all the way round the Earth?

Reveal Answer
ρ=3107 m;n=1.6107 m1\rho=3 \cdot 10^{7} \mathrm{~m} ;|\nabla n|=1.6 \cdot 10^{-7} \mathrm{~m}^{-1}