Physics Optics
The focal length of a convex mirror has a magnitude of 20cm. what is its radius of curvature?
-40 cm
A beam of light traveling in air strikes a glass slab at an angle of incidence less than 90 degrees. After entering the glass slab, what does the beam of light do?
-it bends closer to the normal at the point of contact -it slows down
If the index of refraction of a material is 2, this means that light travels
2 times as fast in vacuum as it does in the material
Which of the following statements about spherical mirrors is correct? A. a concave mirror always produces a real image B. a convex mirror always produces a virtual image C. a concave mirror always produces a virtual image D. a convex mirror always produces a real image E. a convex mirror always produces an upright image
B. a convex mirror always produces a virtual image E. a convex mirror always produces an upright image
Which of the following can form an image? A. a plane mirrow B. a curved mirror C. a lens curved on both sides D. a lens curved only on one side E. all of the above
E. all of the above
Converging lens, such as a typical magnifying glass A. always produce a magnified image B. always produces an image small than the object C. always produces an upright image D. always produces an inverted image (upside down) E. none of the above
E. none of the above
If a spherical convex mirror has a radius of curvature R, the magnitude of its focal length is
R/2
When moonlight strikes the surface of a calm lake, what happens to this light?
Some of it reflects back to the air; some enters the water
Sometimes when you look into a curved mirror you see a magnified image (a great big you) and sometimes you see a diminished image (a little you). If you look at the bottom (convex) side of a shiny spoon, what will you see?
You see a little you, right side up
If an object is placed at the center of curvature of concave mirror, the image formed by the mirror is located
at the center of curvature
You want to create a spotlight that will shine bright beam light with all of the light rays parallel to each other. You have a large concave spherical mirror and a small light bulb. where should you place the lightbulb?
at the focal point of the mirror
A convex lens has a focal length f. If an object is placed at a distance beyond 2f from the lens on the principal axis, the image is located at a distance from the lens
between f and 2f
Singel concave spherical mirrors produce images that
could be smaller than, larger than, or the same size as the actual object, depending on the placement of the object
To shoot a swimming fish with an intense light beam from a laser gun, you should aim
directly at the image
Suppose you place an object in front of a concave mirror. Which of the following is true? A. image of the object will always be smaller than the object B. no matter where you place it, a real image of the object will be formed C. image of the object will always be inverted D. if you position the object between the mirror and the focal point of the mirror, its image must be upright and virtual E. no matter where you place it, image will always be virtual and upright
if you position the object between the mirror and the focal point of the mirror, its image must be upright and virtual
As you walk away from a plane mirror on a wall, the height of your image
is always the same size
A lens can be characterized by its power, which
is the reciprocal of the focal length
A beam of light that is parallel to the principal axis strikes a convex mirror. What happens to the reflected beam of light?
it appears to be coming from the focal point on the other side of the mirror
As an object moves from just outside the focal point of a converging lens to just inside it, the image goes from ____ and ____ to ____ and ____.
large; inverted; large; upright
Light enters glass from air. The angle of refraction will be
less than the angle of incidence
Virtual images can be formed by
plane and curved mirrors, and lenses.
When you look at a fish in a still stream from the bank, the fish appears shallower than it really is due to refraction. From directly above, it appears..
shallower than its real depth because of the index of refraction
Starting from very far away, an object is moved closer and closer to a converging lens, eventually reaching the lens. What happens to its image formed by that lens?
the image eventually changes from real to virtual
A negative magnification for a mirror means that
the image is inverted and the mirror is concave
If you shine a light through an optical fiber, why does it come out the end but not out the sides?
total internal reflection make the light reflect from the sides
An object is placed in front of a convex mirror at a distance larger than twice the magnitude of the focal length of the mirror. The image will appear
upright and enlarged
If an object is placed between a convex lens and its focal point, the image formed is
virtual and upright
When the reflection of an object is seen in a flat mirror, the image is
virtual and upright
Which of the following sets of characteristics describes the image formed by a plane mirror? A. real and inverted B. real and upright C. virtual and upright D. virtual and inverted E. virtual and larger than the object
virtual and upright
Suppose you are standing about 3m in front of a mirror. you can see yourself just from the top of your head to your waist, where the bottom of the mirror cuts off the rest of your image. If you walk one step closer to the mirror
you will see less of your image, with the cutoff rising to be above your waist
If you stand in front of a convex mirror, at the same distance from it as its focal length
you will see your image and you will appear smaller than you