Section 2 Flashcards
Describe Thomas Young’s double slit experiment
Using two slits, young first directed particles at it and noticed it formed a pattern of two lines that aligned with where the slits were. When this was done by shining light at the slits it produced an interference pattern whereby there were alternating light and dark bands on the screen
Describe what happens to waves that are in phase/out of phase
Waves that are in phase will have their amplitudes added to make one large waveform; waves that are out of phase will cancel each other out, resulting in a diminished amplitude
What is a photon?
A quantum of visible light demonstrating both particle and wave properties
Describe the relationship between wavelength and frequency
longer wavelengths have smaller frequencies, and shorter wavelengths have higher frequencies
What range of wavelengths is visible to the human eye?
400nm-700nm
In the range of visible light, which color dominates the lower end of the spectrum, and which color dominates the upper end?
Lower end = blue light
Upper end = red light
How can we differentiate when light acts as a particle or as a wave?
Light will behave like a particle when being emitted by the light source, or when it is interacting with matter (e.g., the retina), but when propagating in space it acts as a wave
Define light absorption
energy that is taken up and is not transmitted at all (object will appear black)
define light reflection
energy that is redirected when it strikes a surface, usually back to its point of origin
How does light reflection relate to the colors we see?
the colors we see are determined by the wavelengths of light that gets reflected
Define light scattering
Energy that is dispersed in an irregular fashion
Why are smaller wavelengths of light more susceptible to scattering?
They are more susceptible to obstacles (e.g., air particles)
Define light transmission
Energy that is passed through a surface (neither reflected nor absorbed)
Define light refraction
Energy that is altered as it passes through another medium (the angle of light changes)
Define specular and diffuse light reflection
Specular: regular and orderly reflection (the smoother the surface it is being reflected on, the more similar the incident and reflective angles will be of the light)
Diffuse: When an object’s surface contains larger irregularities, rays will be reflected in random directions
What is the first tissue in the eye that light will encounter?
The cornea
Why is the minimal light interference when passing through the cornea?
There are no blood vessels in the cornea
What is responsible for the discomfort you feel after wearing contact lenses for too long?
It irritates the transparent nerve endings in your cornea
Where is the aqueous humor located?
between the cornea and lens
What is the role of the aqueous humor?
Provides nourishment to the cornea and lens, and allows the outer layers of the cornea to quickly regenerate if there is damage
What controls the size of the pupil?
The iris
The lens is attached to ciliary muscle via what fibers?
Zonular fibers
What do zonular fibers do?
Stretches the lens when the ciliary muscles are relaxed
What is the main role of the lens?
focuses light on the back of the retina