Physics Ch 25 Refraction Of Light Extras, Not Homework

Front 1

Two diverging light rays, originating from same point, have angle of 10 degrees between them. After rays reflect from a plane mirror, what is angle between them? Construct one possible ray diagram that explains your answer.

Back 1

still ten degrees

Front 2

Two plane mirrors separated by 120 degrees as drawing illustrates. If a ray strikes mirror M1 at 65 degree incidence at what angle does it leave mirror M2?

Back 2

55 degrees

Hint 2

all about the triangles

Front 3

25.6
Figure out which red line will reach P in its entirety

Back 3

neither right now (ask s)

Front 4

Explain why three images come from this

Back 4

you get image from one and image from two and image from what bounces of two from mirror one

Front 5

Define wave front

Back 5

a surface where all points on a wave have the same phase of motion.

Front 6

Define ray

Back 6

Rays are radial lines pointing outward from the source and perpendicular to the wave fronts. They point in the direction of the velocity of the wave.

Front 7

The drawing shows a top view of an object to the right of a plane mirror. An observer looks into the mirror. At what location, A, B, C, or D, does the observer see the image

Back 7

A.

Hint 7

The image is as far behind the mirror as the object is in front of the mirror. In addition, the image and the object lie on the horizontal line that is perpendicular to the mirror

Front 8

A friend is standing 2 m in front of a plane mirror. You are standing 3 m behind your friend. What is the distance between you and the image of your friend?

Back 8

7 m

Hint 8

The image of your friend is 2 m behind the mirror. The distance between you and the mirror is 5 m. Thus, the distance between you and your friend's image is 7 m

Front 9

A friend is standing 2 m in front of a plane mirror. You are standing 3 m behind your friend. What is the distance between you and the image of your friend?

Back 9

7 m

Hint 9

The image of your friend is 2 m behind the mirror. The distance between you and the mirror is 5 m. Thus, the distance between you and your friend's image is 7 m

Front 10

You hold the words top dog in front of a plane mirror. What does the image of these words look like?

Back 10

Front 11

Back 11

55 degrees

Front 12

You hold plane mirror 1.0 m in front eyes and can see a 15 m tree behind. If the mirror is 20.0 cm high and the tree image completely fills the mirror, how far are you from the tree? (study guide practice problem 2)

Back 12

75 m

Front 13

25.2
A person whose eyes are 1.63 m above the floor stands in front of a plane mirror. The top of her head is 0.124 m above her eyes. What is the height of the shortest mirror in which she can see her entire image?

Back 13

8.77×10-1 m

Hint 13

total height over 2 is the height needed

Front 14

Back 14

Front 15

Ray tracing for concave mirror

Back 15

1.first ray comes from top object, parallel to axis, hits mirror and reflects back to f2.second ray comes from top object, seems to come from f, angles to mirror and reflects parallel to axis (topside)3.third ray seems to come from c, hits mirror perpendicularly and is reflected back upon itself and through c

Front 16

Ray trace for convex mirror

Back 16

1.first ray comes from top object, hits mirror, reflects at an angle that makes it seem to originate from f (i.e. velocity is up and to the left, f is to the right of the mirror)2.second ray goes from top of object toward F, is reflected parallel to the principal axis and in line with the top of the object3.third ray comes from top of object, seems to head toward C, hits curvature, reflected back on itself through top of object.
At the convergence of rays on other side of mirror in all convex and with concave if object is between F and mirror. If Object is between F and C, bottom of image is at convergence of rays below y axis and to the left of C. If Object is to the left of C, top of image is at convergence of rays between F and C.

Front 17

Convex mirror used to reflect light from object placed 66 cm in front of mirror. Focal length mirror is f=-46 cm. Find location of image and magnification

Back 17

Location=-27 cmMagnification=.41Image is smaller and upright

Hint 17

Just use mirror equation and then magnification equation (m=-d_i/d_o)

Front 18

CYU 2 What happens if you have an object in between the focal point and C of a concave mirror and move it closer to the mirror but still in between F and C?

Back 18

bigger

Front 19

Example 32.0-cm high object placed 7.10 cm from concave mirror whose R=10.20 cm. Find a) location and b)size

Back 19

Location is d_I=.18105 m, height is –5.1 cm.Image is inverted and large because is between F and C.

Hint 19

Use f=1/2R to find that, C is R. Use mirror equation to find distance and magnification to find height.

Front 20

Rays of light coming from the sun (a very distant object) are near and parallel to the principal axis of a concave mirror. After reflecting from the mirror, where will the rays cross each other at a single point? The rays __________

Back 20

will converge at a focal point (because they are near an axis)

Front 21

Which of the rays in the diagram could not be used to locate the image by the method of ray tracing?

Back 21

any ray leaving object can be used for ray tracing

Front 22

what kind of mirror can produce enlarged image?

Back 22

concave only, when d_o<R

Front 23

An object is placed at a known distance in front of a mirror whose focal length is also known. You apply the mirror equation and find that the image distance is a negative number. This result tells you that __________

Back 23

the image is a virtual image.

Front 24

An object is situated at a known distance in front of a convex mirror whose focal length is also known. A friend of yours does a calculation that shows that the magnification is -2. After some thought, you conclude that __________

Back 24

the magnification should be + 1/2

Hint 24

A convex lens always produces an upright image that is smaller than the object.

Front 25

Light rays that are near and parallel to the principal axis of a concave mirror converge to a point 18 cm in front of the mirror. What is the radius of curvature of the mirror?

Back 25

36 cm

Hint 25

Parallel rays that are near the principal axis converge at the focal point after reflecting from a concave mirror. The radius of curvature is twice the focal length (see Equation 25.1), so R = 2f = 36 cm.

Front 26

An object is placed 20.0 cm in front of a spherical mirror. The image lies 5.0 cm in front of the mirror. What is the focal length f of the mirror? Give your answer to 2 digits, e.g., 6.4.

Back 26

4.0

Front 27

When someone looks into a concave mirror from a distance of 25 cm, a virtual image is produced that is enlarged by a factor of 2. What is the image distance?

Back 27

-50 cm

Front 28

Question 10


A person's face is 30.0 cm in front of a concave makeup mirror, producing an upright image that is 1.50 times as large as the object. What is the mirror's focal length f? Give your answer to 3 digits, e.g., 56.4 or -56.4.

Back 28

90 cm

Front 29

25.16
A mirror produces an image that is located 34.8 cm behind the mirror when the object is located 6.66 cm in front of the mirror. What is the focal length of the mirror? Is it concave or convex?

Back 29

8.24 cm , concave

Hint 29

use 1/f=1/do+1/di to find f, them use m=-d1/do to find m which is positive, and only concave mirrors can produce when the object is placed closer than f to the mirror

Front 30

25.18
A concave mirror has a focal length of 11.9 cm. This mirror forms an image located 24.5 cm in front of the mirror. What is the magnification of the mirror?

Back 30

-1.06

Hint 30

mirror equation to find d0, magnification equation

Front 31

25.20
The outside mirror on the passenger side of a car is convex and has a focal length of -6.24 m. Relative to this mirror, a truck traveling in the rear has an object distance of 12.5 m. Calculate the image distance of the truck.

Back 31

-4.16 m

Hint 31

mirror equation

Front 32

25.22
A concave mirror (f = 48.5 cm) produces an image whose distance from the mirror is one-fourth the object distance. Determine the object distance.

Back 32

2.42×102 cm

Hint 32

sub 4di=do into mirror equation, solve for di, d_o is di times 4

Front 33

25.26
An object is placed the same distance from two spherical mirrors, A and B, and the size of the image is one-third that of the object. The magnifications produced by the mirrors are mA = 3.48 and mB = 1.74. Calculate the ratio fA/fB of the focal lengths of the mirrors.

Back 33

5.97×10-1

Hint 33

see page 799
R=2d_om/1-m
sub -.5R_a=that and solve for m_a
same for m_b
that answer for m_a/" " mb is the answer

Front 34

25.33
A clown is using a concave makeup mirror to get ready for a show and is 26.8 cm in front of the mirror. The image is 63.0 cm behind the mirror. Calculate the focal length of the mirror.

Back 34

46.64 cm

Hint 34

all it is is mirror equation