Chapter 8: Light Technologies Flashcards
Convex Mirror
Bulges outward
The objects appear closer and smaller
Give examples of how convex mirrors are used
i. security devices
ii. side view mirrors on cars
iii. telescopes
Concave Mirror
Curves inward
Objects close to the mirror are seen upright and larger than the object
Objects far away appear inverted and smaller than it is
What is a lens?
A curved piece of transparent material, such as glass or plastic. Light refracts when passing through a lens
Concave lens
Thinner in the middle causing light to spread out
Convex lens
Thicker in the middle causing light to converge
What lens is found in the human eye?
Convex
How does the human eye focus?
Refraction
Retina
Inner most layer
Where light is focused onto
Ciliary muscle
Focuses lens
Changes shape
Cornea
A covering
Begins bending the light
Pupil
Where light goes in
Aqueous humor
Fluid that helps the cornea keep its shape
Iris
Controls how much light enters the eye
Lens
Focuses the image (can change shape to do so)
Optic disc
Where the optic nerve connects to the brain also called the blindspot
Optic Nerve
Takes info from the retina to the brain
Sclera
Protective covering
If you are near sighted your eye is…
too long
If you are far sighted your eye is too…
short
What lens corrects near sightedness? How?
Concave by pushing the image a little further back in the eye
What lens corrects far sightedness? How?
Convex lens cause the image to not fall behind the retina
Why do people need reading glasses as they get older?
Because their ciliary muscles stiffen. They usually need convex lens.
What is the far point?
The farthest point an image is in focus
What is iris reflex?
When the iris adjusts naturally to available light,
Statement below
Tear fluid helps refract light
Remember that!!!!!!!!!!!!!
When was the first telescope invented?
1680
What types of telescopes are there and what do they use?
Refracting = Lens (specifically convex) Reflecting = Mirror (specifically concave)
Further explanation on reflecting:
The mirror is called a primary or objective mirror. It forms a real image, which is then magnified by the eye piece lens.
Further explanation on refracting:
In a refracting telescope the convex lens (also called the objective lens) is used to focus light. A second lens called the eye piece lens works like a magnifying glass to enlarge the image.
What are binoculars?
A pair of reflecting telescopes. The plane mirrors are replaced with 2 prisms.
How are microscopes and telescopes similar? How are they different?
A. They both see things up close and both have mirrors.
B. Telescopes look at things that are far away and normally quite large. Microscopes look at things that are microscopic.
Attitude
In optics, the position (upright or upside down) of an image in relation to the object it reflects
Real image
Virtual image
Real image appears in front and is found with concave mirrors
Virtual image appears behind and is found with plane mirrors and convex mirrors.
