Vocab. I
Objects that do not allow any light to pass through them
What are opaque objects?
A pencil look broken when it is placed in a cup of water. Why?
Light travels slower through water than through air. As the light enters the glass of water it slows down (changes direction) and as it leaves the glass it speeds up again – therefore making the pencil look as though it is bent!
The part of the eye that first refracts light
What is the cornea?
Some animals see better at night because they have more of this structure.
What are rods (in the retina)?
This lens is wider at the ends and thinner in the middle.
What is concave?
What do you call objects that allow some light to pass through them?
What is translucent objects?
The part of the eye where the light-sensitive rods and cones are and where the image is formed
What is the retina?
Animals with better night vision may have this structure which is blue-green and reflects light.
What is a tapetum?
If a light ray hits a mirror at an angle of 35 degrees, at what angle will it reflect off the mirror?
What is 35 degrees?
What is the term for when light waves bend when passing from one medium to another?
Refraction
Light can travel through objects. It can also do 3 different things. What are they?
What is be reflected, refracted, and absorbed?
The part of the eye that regulates how much light enters the pupil
What is the iris?
List the colors of visible light in order of decreasing wavelength.
Red, orange, yellow, green, blue, indigo, violet
Which visible light wavelength is closest to the ultraviolet wavelength? It has a higher frequency than the other colors in visible light.
What is violet?
Your friend is wearing a red shirt. What is the term for when the red wavelengths bounce off the shirt?
What is reflection?
You are underwater, wearing goggles. You see a plastic torpedo on the bottom of the pool. The light reflected off the torpedo has to travel through three media in order to get to your eye. List the media in order.
1. water 2. plastic on goggles 3. air between the plastic googles and eye
Light enters the eye and is refracted by the cornea. it is refracted again after passing through the aqueous humor and pupil. Where does this 2nd refraction occur?
What is the lens?
You are looking at a banana. Explain which colors are being absorbed and reflected.
Yellow is reflected and ROGBIV are absorbed
What is the type of lens that is thicker in the middle than on the sides? It converges the light rays after the light leaves the lens?
What is a convex lens?
I shine a light through an object. The light scatters after being transmitted through the object. What type of object is it?
What is translucent?
When light hits an object, it either reflects, and stays as light energy, refracts and passes through the object, or is absorbed by the object. When it's absorbed, what is the light changed into?
What is, the light is converted into heat energy, and the object heats up.
At noon, you see a tree with green leaves. Describe the image that would form on your retina. What happens to this image?
What is upside down, smaller, and reversed? Image travels as an electrical signal via the optic nerve to the brain.
This occurs when the shape of your eye causes light rays to refract incorrectly, focusing images in front of your retina instead of on your retina.
What is nearsightedness? Could you draw what the light rays would do?