Reflection and Refraction

A series of flashcards to review important concepts and principles related to reflection and refraction of light.

What is a ray of light?

A narrow beam of parallel light that can be represented as a single line on a ray diagram.

What is reflection?

The bouncing of light off the surface of an object which allows us to see it.

What are the two types of reflection?

Regular (specular) reflection and diffused reflection.

What is specular reflection?

The reflection of parallel rays of light from a particular source in one direction.

What is diffused reflection?

The irregular scattering of light rays in different directions.

What is the normal in the context of reflection?

A line that is perpendicular to the surface at the point of incidence.

What does the law of reflection state?

The angle of incidence is equal to the angle of reflection.

What is refraction?

The bending of a light ray as it passes from one medium to another.

How does light behave when entering an optically denser medium?

It bends towards the normal.

What is Snell's law?

The ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant.

What is a critical angle?

The angle of incidence in the optically denser medium for which the angle of refraction is 90 degrees.

What are the conditions for total internal reflection?

Light must travel from a denser medium to a less dense medium, and the angle of incidence must be greater than the critical angle.

What is the use of optical fibres?

To transmit light signals with minimal loss and distortion.

What is the refractive index for a medium?

The ratio of the speed of light in free space to the speed of light in the medium.

In which direction does light bend when moving from a less dense to a denser medium?

It bends towards the normal.

What happens to light when it exceeds the critical angle in total internal reflection?

It reflects back inside the denser medium without emerging.