The human eye and the colorful world long 4

Question 1

What is angle of the prism ?

Answer 1

A triangular glass prism. It has two triangular bases and three rectangular lateral surfaces. These surfaces are inclined to each other. The angle between its two lateral faces is called the angle of the prism.

Question 2

What is atmospheric refraction ?

Answer 2

Atmospheric refraction is the deviation of light
from a straight line as they pass through the atmosphere due to the variation in air density as a function of height. This refraction is caused by the velocity of light through air decreasing with increased density.

Question 3

What causes the twinkling of stars ?

Answer 3

When starlight enters the Earth’s atmosphere, it bends due to refraction, making the star appear slightly different from its actual position. The atmosphere’s bending of light toward the normal causes the star to seem higher when near the horizon. The apparent star position changes due to shifting atmospheric conditions, leading to fluctuating starlight. This causes the star to flicker and exhibit varying brightness, resulting in the twinkling effect.