Light&sound Flashcards
What form of energy is light?
Electromagnetic radiation
Where is the normal located?
At a right angle from the interface
What is the light entering a glass prism called?
Incident Ray
What is the light called that travels through a glass prism called?
Refracted Ray
Bending of light is called
Refraction
When light travels from a less dense medium to a more dense medium, the Ray bends…
Towards the normal
When a Ray moves from a more dense substance to a less dense substance the Ray…
Bends away from the normal.
Light travels at ‘’ speed through air
Higher
What objects fit under the transparent category?
Clear glass, shallow water
What objects fit under the opaque category
Bricks, a piece of wood, a desk and a football
What objects fit under the translucent category?
Tissue paper,fingernails,frosted glass
When light hits an transparent surface it…
Is transmitted through it or reflected off it
When light hits a translucent surface it…
Is transmitted through it or reflected off it.
When light hits an opaque surface it…
Is absorbed into it or reflected off it
How fast do light waves travel per second?
300,000km per second
When light is shone on a mirror, what is the Ray called that leaves the mirror?
The reflected Ray.
Why does an object appear closer when looking at it through water?
Because reflected light off the object bends away from the normal when it enters the air.
When can total internal reflection occur?
Total internal reflection can only occur when light passes through a substance of lower refractive index. TIR occurs because the Ray can no longer refract, so instead it totally internally refracts: it has nowhere else to go.
What medium doe slight travel the slowest in?
A Dimond. It has a higher refractive index. And the speed of light travels at 124,000 km/s
When the refractive index is higher it means?….
That the medium is denser and light travels slower through it.
Total internal reflection never occurs when light travels into a substance of greater refractive index because…
The refracted Ray bends towards the normal through the interface.
What is the cornea and where is it located?
The cornea bends light into the lens. It lies in front of the iris (coloured part of the eye)
What is the lens?
A flexible structure that enables light to be focused on the retina.
What is the retina and where is it located?
The cells on the retina called cone rod cells absorb light rays and turn them into electrical signals. The retina is located at the back of the eye.
What is vitreous humour?
Clear fluid between the lens and the retina.
What is the white of the eye called?
Sclera.
What does the pupil do?
Controls the amount of light entering the eye.
Where do the electrical signals that the retina created travel?
To the optic nerve. It travels the signals to the brain from the retina
Longsightedness means a person struggles to see images…
Closer to them
Shortsightedness means-
a person struggles to see an image further away from them.
