Reflection and Refraction Flashcards
What does a ray diagram show?
A ray diagram shows how light travels, including what happens when it reaches a surface.
What is the angle of incidence?
Angle I = Angle between the normal and the incident ray.
How do you draw lines in a ray diagram?
- as a straight line
* with an arrowhead pointing in the direction that the light travels
What is the law of reflection?
The law of reflection: when light reaches a mirror, it reflects off the surface of the mirror
The law of reflection states that the angle of incidence equals the angle of reflection, i = r. It works for any angle.
For example: the angle of reflection is 30° if the angle of incidence is 30°
What is the incident ray?
the incident ray is the light going towards the mirror
What is the angle of incidence?
Angle I = Angle between the normal and the incident ray.
What is the reflected ray?
the reflected ray is the light coming away from the mirror
What is the angle of reflection?
Angle R = The angle between the reflected ray and the normal (the imaginary line drawn at 90 degrees to the reflecting surface).
Describe the image in a plane mirror.
Inverted (back to front)
Virtual (cannot be cast on to a screen)
Describe the “normal” line in a ray diagram
the dashed line is called the normal, drawn at 90° to the surface of the mirror
What is specular reflection?
The reflection of light from a flat surface such as a mirror
What happens when water waves hit a surface?
They are REFLECTED.
The angle of incidence is the same as the angle of reflection.
We usually look at our reflection in a flat mirror. This type of mirror is a…
a plane mirror
When light goes from a less dense medium to a more dense medium…
… light bends towards the normal
When light goes from a more dense medium to a less dense medium…
… light bends away from the normal
