ap physics b lecture notes chapter 23 mirrors and lenses

AP Physics B Lecture Notes

Chapter 23Mirrors and Lenses

23-01 Flat Mirrors

23-02 Images Formed by Spherical Mirrors

23-03 Concave Mirrors and Sign Conventions

23-06 Thin Lenses

Mirrors and Lenses

Sections

Flat Mirrors

A

B

2A

2B

What length is required for a full length mirror?

Flat Mirrors

Multiple Images

Flat Mirrors

Multiple Images

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Images Formed by Spherical Mirrors

Area of Convergence

Concave Mirror

Principle Focal Point 2R

f


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.

Concave Mirror

Light Source at the Focal Point

Produces Parallel Rays of Light



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.




Concave Mirror

Real Image


Concave Mirror

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Concave Mirror

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Mirror Equation

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Concave Mirror

Virtual Image


Concave Mirror

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Concave Mirror

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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.

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?

Images Formed by Spherical Mirrors (Problem)


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.





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.

Convex Mirror


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Convex Mirror

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Convex Mirror

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Convex Mirror

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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.

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?

Images Formed by Spherical Mirrors (Problem)


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

Thin 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.

Double Convex Lens

Focal Point

Thin 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.

Real Image

Double Convex Lens

Thin Lenses

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Double Convex Lens

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Thin Lenses

Convex Lens

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Thin Lenses

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Lens Equation

Double Convex Lens

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Thin Lenses

Convex Lens

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Convex Lens

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Convex Lens

Lens Equation

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Thin Lenses

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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.

Virtual Focal Point

Concave Lens

Thin Lenses

Concave Lens

Virtual Image

Thin Lenses

Concave Lens

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Thin Lenses

Concave Lens

Similar Triangles

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Thin Lenses

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Concave Lens

Lens Equation

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Thin 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.

ap physics b lecture notes chapter 23 mirrors and lenses

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