8.1 In the diagram below, a ray of light moves from water into air, with an angle of incidence of 49° - NSC Technical Sciences - Question 8 - 2021 - Paper 2

In the new diagram, draw the incident ray making an angle of 65° with the normal as it enters the air. The refracted ray should bend away from the normal at the boundary, while the reflected ray should also be marked as reflecting at 65°. This shows that total internal reflection occurs since the angle exceeds the critical angle.

This phenomenon is called total internal reflection.

Dispersion is the process by which white light separates into its component colors or wavelengths when it passes through a medium, such as a prism.

In the ray diagram, illustrate an incident ray of white light entering the triangular prism. Upon entering, the light will refract and separate into its component colors. The color that is refracted the MOST is violet, while the color that is refracted the LEAST is red.

There are five other colors in the spectrum besides red and violet: orange, yellow, green, blue, and indigo.

Refraction is the bending of light as it passes from one medium to another with different optical densities, resulting from a change in the speed of light.

White light spreads out into different colors because each color has a different wavelength and therefore travels at different speeds in the prism. As light enters the prism, shorter wavelengths (like violet) are refracted more than longer wavelengths (like red), causing the different colors to spread out and form a spectrum.