Question

Your mother has brought a red dress for you. Write a dairy entry to share your feeling.

Answer 1

Explanation:

Snell's law from geometrical optics states that the ratio of the angles of incidence θ1 and of the angle of refraction θ2 as shown in figure1, is the same as the opposite ratio of the indices of refraction n1 and n2.

sinθ1sinθ2=n2n1

figure 1

(figure originally from wikimedia)

Now let P be a point in one medium (with refraction index n1) and Q a point in the other one as in the figure. My question is, is there is a nice geometrical construction (at best using only ruler and compass) to find the point O in the figure such that Snell's law is satisfied. (Suppose you know the interface and n2/n1)?

Edit A long time ago user17762 announced to post a