Deck 25: The Reflection of Light: Mirrors

Question 1

In the figure, Joel is using a device known as a periscope to observe an object, represented by an upright arrow.The periscope contains two plane mirrors tilted at an angle of 45° relative to Joel's line of sight.Which one of the following pairs of characteristics of the final image that Joel looks at is correct relative to those of the object?

A)inverted, real
B)upright, enlarged
C)inverted, smaller
D)inverted, same size
E)upright, virtual

Answer 1

upright, virtual

Question 2

Santa Claus looks at his reflection in a spherical Christmas tree ornament.Which one of the following statements concerning Santa's image is true?

A)The image must be real.
B)The image is farther from the ornament than Santa is.
C)The image is larger than Santa.
D)The image must be inverted.
E)The image must be smaller than Santa.

Answer 2

The image must be smaller than Santa.

Question 3

The radius of curvature of a spherical convex mirror is 52 cm.What is its focal length?

A)+26 cm
B)-26 cm
C)+52 cm
D)-52 cm
E)+104 cm

Answer 3

-26 cm

Question 4

25-1
An object is placed in front of a concave spherical mirror as shown below.The three rays 1, 2, and 3, leave the top of the object and, after reflection, converge at a point on the top of the image.Ray 1 is parallel to the principal axis, ray 2 passes through F, and ray 3 passes through C.
Which ray(s) will reflect back on itself (themselves)?

A)1 only
B)2 only
C)3 only
D)both 1 and 2
E)1, 2, and 3

Question 5

A ray of light is reflected from two plane mirror surfaces as shown in the figure.What are the correct values of $\alpha$ and $\beta$ ?

A)
B)
C)
D)
E)

Question 6

Which one of the following statements concerning a convex mirror is true?

A)A convex mirror can form a real image.
B)A convex mirror must be spherical in shape.
C)The image produced by a convex mirror will always be inverted relative to the object.
D)A convex mirror produces a larger image than a plane mirror does for the same object distance.
E)The image a convex mirror produces is closer to the mirror than it would be in a plane mirror for the same object distance.

Question 7

The focal length of a spherical concave mirror is 25 cm.What is its radius of curvature?

A)5 cm
B)10 cm
C)25 cm
D)40 cm
E)50 cm

Question 8

Makenzie walks directly toward a plane mirror at a speed of 0.30 m/s.Determine the speed of the image relative to her.

A)0.15 m/s
B)0.30 m/s
C)0.60 m/s
D)0.90 m/s
E)1.2 m/s

Question 9

Five balls labeled A, B, C, D, and E are placed in front of a plane mirror as shown in the figure.Which ball(s) will the observer, in the position shown, see reflected in the mirror?

A)A only
B)C only
C)A and B
D)A, B, D and E
E)A, B, C, D and E

Question 10

25-1
An object is placed in front of a concave spherical mirror as shown below.The three rays 1, 2, and 3, leave the top of the object and, after reflection, converge at a point on the top of the image.Ray 1 is parallel to the principal axis, ray 2 passes through F, and ray 3 passes through C.
Which ray(s) will pass through F after reflection?

A)1 only
B)2 only
C)3 only
D)both 1 and 2
E)1, 2, and 3

Question 11

An object is placed near two perpendicular plane mirrors as shown in the figure.How many images will be formed?

A)1
B)2
C)3
D)4
E)5

Question 12

Which one of the following statements is not a characteristic of a plane mirror?

A)The image is real.
B)The magnification is +1.
C)The image is always upright.
D)The image is reversed right to left.
E)The image and object distances are equal in magnitude.

Question 13

A concave mirror has a radius of curvature of 60.0 cm.How close to the mirror should an object be placed so that the rays travel parallel to each other after reflection?

A)10.0 cm
B)15.0 cm
C)30.0 cm
D)45.0 cm
E)60.0 cm

Question 14

An object is placed 1 m in front of a plane mirror.An observer stands 3 m behind the object.For what distance must the observer focus his eyes in order to see the image of the object?

A)1 m
B)2 m
C)3 m
D)4 m
E)5 m

Question 15

Which one of the following phrases most accurately describes the term wave front?

A)the surface of a plane mirror
B)the surface of a convex mirror
C)a surface upon which a wave is incident
D)a surface of constant phase within a wave
E)a surface that is parallel to the direction of wave propagation

Question 16

Which one of the following statements concerning rays is false?

A)Rays point in the direction of the wave velocity.
B)Rays point outward from the wave source.
C)Rays are parallel to the wave front.
D)Rays are radial lines that originate from a point source of waves.
E)Rays for a plane wave are parallel to each other.

Question 17

Which one of the following phrases most accurately describes paraxial rays?

A)rays that pass through the principal focus
B)any rays that are parallel to the principal axis
C)rays that come to a focus on the principal axis
D)rays close to the principal axis and parallel to it
E)rays close to the principal axis, but not necessarily parallel to it

Question 18

Which one of the following statements concerning the image formed by a concave spherical mirror is true?

A)When the object distance is less than the focal length, the image is virtual.
B)When the object distance is larger than the focal length, the image is virtual.
C)When the object is at the center of curvature, the image is formed at infinity.
D)When the object distance is less than the focal length, the image is inverted relative to the object.
E)When the object distance is larger than the focal length, the image is upright relative to the object.

Question 19

Two plane mirrors are connected perpendicular to each other, as shown in the figure.If a person looks into the corner at the image straight ahead of him and closes his left eye as shown, which one of the following statements is true?

A)The left eye of the image is closed.
B)The right eye of the image is closed.
C)Both eyes of the image are open.
D)Both eyes of the image are closed.
E)There is no image straight ahead of him, so this question is meaningless.

Question 20

Two mirrors are arranged as shown in the drawing.Light is incident from the right on the first mirror at an angle of 70°.The light reflects toward the second mirror and is reflected at angle $\theta$ .Determine the angle $\theta$ .

A)25°
B)65°
C)45°
D)35°
E)55°

Question 21

A 0.127-m pencil is oriented perpendicular to the principal axis of a concave spherical mirror that has a radius of curvature of 0.300 m.What are the image distance and the image height if the pencil is 0.250 m from the mirror?

A)
B)
C)
D)
E)

Question 22

A concave mirror has a radius of curvature of 20 cm.For which one of the following object distances will the image be real, inverted and smaller than the object?

A)5 cm
B)10 cm
C)15 cm
D)18 cm
E)25 cm

Question 23

An object is placed 20.0 cm in front of a convex spherical mirror with radius of curvature 60.0 cm.Which one of the following phrases best describes the image?

A)virtual and located at infinity
B)real and located 12 cm from the mirror
C)real and located 17 cm from the mirror
D)virtual and located 12 cm from the mirror
E)virtual and located 17 cm from the mirror

Question 24

A convex mirror with a focal length of 58 cm is used to form an image that is 29 cm behind the mirror.What is the object distance?

A)+22 cm
B)+15 cm
C)+69 cm
D)+28 cm
E)+58 cm

Question 25

An object is placed 20 cm in front of a concave spherical mirror that has a radius of curvature 60 cm.Which one of the following phrases best describes the image?

A)virtual and located at infinity
B)real and located 60 cm from the mirror
C)real and located 120 cm from the mirror
D)virtual and located 60 cm from the mirror
E)virtual and located 120 cm from the mirror

Question 26

25-1
An object is placed in front of a concave spherical mirror as shown below.The three rays 1, 2, and 3, leave the top of the object and, after reflection, converge at a point on the top of the image.Ray 1 is parallel to the principal axis, ray 2 passes through F, and ray 3 passes through C.
Which one of the following groups of terms best describes the image?

A)real, upright, enlarged
B)real, inverted, reduced
C)virtual, upright, enlarged
D)real, inverted, enlarged
E)virtual, inverted, reduced

Question 27

A convex mirror has a radius of curvature of 0.50 m.Where must an object be placed in front of the mirror such that the image is formed 0.15 m behind the mirror?

A)0.38 m
B)0.19 m
C)0.77 m
D)0.093 m
E)0.57 m

Question 28

A dime is placed in front of a concave mirror that has a radius of curvature R = 0.30 m.The image of the dime is inverted and three times the size of the dime.Determine the distance between the dime and the mirror.

A)0.20 m
B)0.15 m
C)0.10 m
D)0.60 m
E)0.45 m

Question 29

A 6.0-ft tall football player stands in front of a plane mirror.How tall must the mirror be so that the football player can see his full-sized image?

A)2.0 ft
B)2.5 ft
C)3.0 ft
D)3.5 ft
E)6.0 ft

Question 30

A spherical concave mirror has a radius of curvature of 6.0 cm.At what distance from the mirror should a 6.0-cm object be placed to obtain an image that is 48 cm tall?

A)1.3 cm
B)3.6 cm
C)4.2 cm
D)5.3 cm
E)6.8 cm

Question 31

A concave mirror in an amusement park has a radius of curvature of 4.0 m.A child stands in front of the mirror so that she appears 3.0 times taller than her actual height.If the image is upright, how far is she standing from the mirror?

A)1.1 m
B)1.3 m
C)2.8 m
D)3.0 m
E)4.5 m

Question 32

An object is 1.0 m in front of a mirror.A virtual image is formed 10.0 m behind the mirror.What is the radius of curvature of the mirror?

A)0.56 m
B)1.1 m
C)2.2 m
D)4.4 m
E)This problem cannot be solved without more information.

Question 33

The inverted image of a light bulb is formed on a screen located 9.00 m from a spherical mirror.The image is 4.00 times larger than the light bulb.Determine the object distance and the type of mirror used.

A)+0.444 m, concave
B)+2.25 m, concave
C)+36.0 m.concave
D)+0.0278 m, convex
E)+36.0 m, convex

Question 34

A woman stands 2.0 m in front of a convex mirror and notices that her image height is 1/4 of her actual height.Determine the radius of curvature of the mirror.

A)0.67 m
B)1.3 m
C)2.0 m
D)4.0 m
E)6.0 m

Question 35

The table below lists object and image distances for five objects placed in front of mirrors.For which one of the following cases is the image formed by a convex spherical mirror?

A)
B)
C)
D)
E)

Question 36

A convex mirror in an amusement park has a radius of curvature of 3.00 m.A man stands in front of the mirror so that his image is half as tall as his actual height.At what distance must the man focus his eyes in order to see his image?

A)2.25 m
B)3.00 m
C)4.50 m
D)5.00 m
E)6.75 m

Question 37

A plane mirror is 6 ft tall.What is its focal length?

A)zero feet
B)3 ft
C)6 ft
D)12 ft
E)infinity

Question 38

A rubber ball is held 4.0 m above a concave spherical mirror with a radius of curvature of 1.5 m.At time equals zero, the ball is dropped from rest and falls along the principal axis of the mirror.How much time elapses before the ball and its image are at the same location?

A)0.30 s
B)0.55 s
C)0.63 s
D)0.71 s
E)0.90 s

Question 39

Which one of the following statements concerning a virtual image produced by a mirror is true?

A)A virtual image is always larger than the object.
B)A virtual image is always smaller than the object.
C)A virtual image is always upright relative to the object.
D)A virtual image is always inverted relative to the object.
E)A virtual image can be photographed or projected onto a screen.

Question 40

A concave mirror is found to focus parallel rays at a distance of 18 cm.Where is the image formed when an object is placed 6.0 cm in front of the mirror?

A)11 cm in front of the mirror
B)18 cm behind the mirror
C)3.6 cm in front of the mirror
D)9.0 cm behind the mirror
E)9.0 cm in front of the mirror

Question 41

25-2
An object with a height of 3.0-cm is placed 8.0 cm in front of a mirror.The virtual image is 4.0 cm further from the mirror when the mirror is concave than when it is planar.
Determine the image height in the concave mirror.

A)0.5
B)1.5
C)2.0
D)3.0
E)4.5

Question 42

25-2
An object with a height of 3.0-cm is placed 8.0 cm in front of a mirror.The virtual image is 4.0 cm further from the mirror when the mirror is concave than when it is planar.
Determine the focal length of the concave mirror.

A)6.0 cm
B)12 cm
C)24 cm
D)48 cm
E)96 cm