Chapter 1: Light&Eye Flashcards
What is a light wave also known as?
Light rays
What is specular reflection?
When all light reflects off at the same angle and directions, only on smooth surfaces
What is diffuse reflection?
Only happens on rough surfaces, the light is reflected in scattered directions and angles
What’s the law of reflection?
The angle of incidence is always equal to the angle of reflection
What is refraction?
When light bends as it crosses a boundary
What will light only travel through?
Transparent material, not anything opaque
What’s a medium?
Any substance that light travels through
Which way does light bend when going from a less dense medium to a more dense medium?
Towards the normal(e.g: glass to air)
Which way does light bend when it goes from a more dense medium to a less dense medium?
Away from the normal
What happens in refraction?
Light hits the “glass” at an angle, slows down and bends, the Ray bends towards the normal and speeds up at the same angle
Why do we see thing?
Because of reflection, when luminous objects produce light it’s reflects off non-luminous objects, it reflects into our eyes
Function of pupil?
Let’s light in
Function of ciliary muscle?
Adjusts the focus by pulling the lens thin or squashing it fat
Function of iris?
Determines how much light gets in
Function of retina?
Contains photoreceptor cells that detect dim light(rods) or colour (cones)
Function of the cornea and lens?
Refracts/reflects light
What’s the nerve that sends messages to brain from eye?
Optic nerve
What does long-sighted mean?
Can’t see things that are closer so your lens focuses behind the retina
What does short-sighted mean?
Can’t see things far away so lens focuses before retina
Colours of rainbow in order
Red Orange Yellow Green Blue Indigo Violet
How do we see white light?
No colours are absorbed and all reflected
How do we see black light?
All colours are absorbed and none are reflected?
How do we see a particular colour? For example blue
Blue light is reflected and the rest are absorbed
What are shadows?
Places where light is blocked
How does light travel
Straight lines
