Mirrors and Lenses

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The object is outside the center of curvature of the mirror

The image is real, inverted, and smaller than the object

Slide 17

Ray Diagram for a Concave Mirror, p < f

The object is between the mirror and the focal point

The image is virtual, upright, and larger than the object

Slide 18

Ray Diagram for a Convex Mirror

The object is in front of a convex mirror

The image is virtual, upright, and smaller than the object

Slide 19

Notes on Images

With a concave mirror, the image may be either real or virtual

If the object is outside the focal point, the image is real

If the object is at the focal point, the image is infinitely far away

If the object is between the mirror and the focal point, the image is virtual

With a convex mirror, the image is always virtual and upright

As the object distance increases, the virtual image gets smaller

Slide 20

Chapter 23 Problem 13

A concave makeup mirror is designed so that a person 25 cm in front of it sees an upright image magnified by a factor of two. What is the radius of curvature of the mirror?

Slide 21

Images Formed by Refraction

Rays originate from the object point, O, and pass through the image point, I

When n2 > n1, real images are formed on the side opposite from the object

Slide 22

Sign Conventions for Refracting Surfaces

Slide 23

Flat Refracting Surface

The image formed by a flat refracting surface is on the same side of the surface as the object

The image is virtual

When n1 > n2, the image forms between the object and the surface

When n1 > n2, the rays bend away from the normal

Slide 24

Chapter 23 Problem 22

A goldfish is swimming inside a spherical bowl of water having an index of refraction n = 1.333. Suppose the goldfish is p = 10.0 cm from the wall of a bowl of radius |R| = 15.0 cm, as in the figure. Neglecting the refraction of light caused by the wall of the bowl, determine the apparent distance of the goldfish from the wall according to an observer outside the bowl.

Slide 25

Atmospheric Refraction

There are many interesting results of refraction in the atmosphere