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