# Chapter 23 Mirrors and Lenses

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Chapter 23 Mirrors and Lenses
AP Physics B Lecture Notes

Mirrors and Lenses Sections 23-01 Flat Mirrors
Images Formed by Spherical Mirrors Concave Mirrors and Sign Conventions 23-06 Thin Lenses

Flat Mirrors What length is required for a full length mirror? A B

Flat Mirrors Multiple Images

Flat Mirrors Multiple Images

Images Formed by Spherical Mirrors
Area of Convergence

Images Formed by Spherical Mirrors
Area of Convergence

Images Formed by Spherical Mirrors
Concave Mirror Principle Focal Point

Chapter 23 Mirrors and Lenses
A light ray, traveling parallel to a concave mirror's axis, strikes the mirror's surface near its midpoint. After reflection, this ray (A) again travels parallel to the mirror's axis. (B) travels at right angles to the mirror's axis. (C) passes through the mirror's center of curvature. (D) passes through the mirror's focal point.

Images Formed by Spherical Mirrors
Concave Mirror Light Source at the Focal Point Produces Parallel Rays of Light

Chapter 23 Mirrors and Lenses
A light ray, traveling obliquely to a concave mirror's surface, crosses the axis at the mirror's focal point before striking the mirror's surface. After reflection, this ray (A) travels parallel to the mirror's axis. (B) travels at right angles to the mirror's axis. (C) passes through the mirror's center of curvature. (D) passes through the mirror's focal point.

Images Formed by Spherical Mirrors
Concave Mirror Real Image

Images Formed by Spherical Mirrors
Concave Mirror q p f h h’

Images Formed by Spherical Mirrors
Concave Mirror q p f h h’

Images Formed by Spherical Mirrors
Mirror Equation

Images Formed by Spherical Mirrors
Concave Mirror Virtual Image

Images Formed by Spherical Mirrors
Concave Mirror p f h h’ q

Images Formed by Spherical Mirrors
q Concave Mirror

Images Formed by Spherical Mirrors

Chapter 23 Mirrors and Lenses
A object is placed between a convex lens and its focal point. The image formed is (A) virtual and inverted. (B) virtual and erect. (C) real and erect. (D) real and inverted.

Images Formed by Spherical Mirrors (Problem)
A mirror at an amusement park shows an upright image of any person who stands 1.4 m in front of it. If the image is three times the person’s height, what is the radius of curvature?

Chapter 23 Mirrors and Lenses
A light ray, traveling obliquely to a concave mirror's axis, crosses the axis at the mirror's center of curvature before striking the mirror's surface. After reflection, this ray (A) travels parallel to the mirror's axis. (B) travels at right angles to the mirror's axis. (C) passes through the mirror's center of curvature. (D) passes through the mirror's focal point.

Chapter 23 Mirrors and Lenses
If you stand in front of a concave mirror, exactly at its focal point, (A) you will see your image at your same height. (B) you won't see your image because there is none. (B) you will see your image, and you will appear smaller. (C) you will see your image and you will appear larger.

Images Formed by Spherical Mirrors
Convex Mirror

Images Formed by Spherical Mirrors
Convex Mirror q p f

Images Formed by Spherical Mirrors
Convex Mirror h h’ p q f

Images Formed by Spherical Mirrors
Convex Mirror h h’ p q

Images Formed by Spherical Mirrors
q

Chapter 23 Mirrors and Lenses
If you stand in front of a convex mirror, at the same distance from it as its radius of curvature, (A) you won't see your image because there is none. (B) you will see your image at your same height. (C) you will see your image and you will appear smaller. (D) you will see your image and you will appear larger.

Images Formed by Spherical Mirrors (Problem)
The image of a distant tree is virtual and very small when viewed in a curved mirror. The image appears to be 18 cm behind the mirror. What kind of mirror is it, and what is its radius of curvature?

Chapter 23 Mirrors and Lenses
A single convex spherical mirror produces an image which is (A) always virtual. (B) always real. (C) real only if the object distance is less than f. (D) real only if the object distance is greater than f.

Concave Mirrors and Sign Conventions

Thin Lenses Thin lenses are those whose thickness is small compared to their radius of curvature. They may be either converging (a) or diverging (b).

Chapter 23 Mirrors and Lenses
Lenses that are thicker at the center (A) spread out light rays. (B) bend light rays to a point beyond the lens. (C) have no effect on light rays. (D) reflect light rays back.

Thin Lenses Double Convex Lens Focal Point

Chapter 23 Mirrors and Lenses
A light ray, traveling parallel to the axis of a convex thin lens, strikes the lens near its midpoint. After traveling through the lens, this ray emerges traveling obliquely to the axis of the lens (A) such that it never crosses the axis. (B) crossing the axis at a point equal to twice the focal length. (C) passing between the lens and its focal point. (D) passing through its focal point.

Thin Lenses Double Convex Lens Real Image

Thin Lenses Double Convex Lens f p q h’ Similar Triangles h

Thin Lenses Convex Lens p q Similar Triangles h f f h’

Thin Lenses Double Convex Lens Lens Equation

Thin Lenses Convex Lens f f Similar Triangles h h p q

Thin Lenses Convex Lens f f Similar Triangles h h p q

Thin Lenses Convex Lens f q h p Lens Equation

Chapter 23 Mirrors and Lenses
A convex lens has a focal length f. An object is placed between f and 2f on the axis. The image formed is located (A) at 2f. (B) between f and 2f. (C) at f. (D) at a distance greater than 2f from the lens.

Thin Lenses (Problem) A converging lens has a focal length of 20.0 cm. a) Locate the images for object distances of 40.0 cm, b) Locate the images for object distances of 20.0 cm. c) Locate the images for object distances of 10.0 cm.

Thin Lenses Concave Lens Virtual Focal Point

Thin Lenses Concave Lens Virtual Image

Thin Lenses Concave Lens h h’ p f q h Similar Triangles

Thin Lenses Concave Lens h h’ p f q Similar Triangles

Thin Lenses Concave Lens Lens Equation

Chapter 23 Mirrors and Lenses
The images formed by concave lenses (A) are always real. (B) are always virtual. (C) could be real or virtual; it depends on whether the object distance is smaller or greater than the focal length. (D) could be real or virtual, but always real when the object is placed at the focal point.

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