20 Reflection & Refraction

Question 1

branch of optics; studies lights as rays

Answer 1

geometric optics

Question 2

direction and path of light as it travels and interacts with boundaries

Answer 2

geometric optics

Question 3

light travels in straight lines

Answer 3

rectilinear propagation

Question 4

used to analyze mirrors, lenses, and image formation

Answer 4

geometric optics

Question 5

object that radiates light equally in all directions

Answer 5

representation of point as a light src

Question 6

light spreads out radially from the source

Answer 6

representation of point as a light src

Question 7

intensity decreases with distance due to what law

Answer 7

inverse square law

Question 8

useful for explaining shadows

Answer 8

representation of point as a light src

Question 9

interaction of light from optical surfaces

Answer 9

• partly/totally reflected
• partly transmitted via refraction at interface, enter second medium
• scattered in random directions at the interface
• partly absorbed in either medium

Question 10

ray of light coming toward a surface

Answer 10

incident ray

Question 11

ray of light bouncing off surface

Answer 11

reflected ray

Question 12

imaginary line perpendicular to surface at pt of reflection

Answer 12

normal line

Question 13

angle between incident ray and normal

Answer 13

angle of incidence (θ1)

Question 14

angle between reflected ray and normal

Answer 14

angle of reflection (θ2)

Question 15

exact spot where incident ray hits surface

Answer 15

pt of reflection

Question 16

surface that can reflect light (ex. mirror)

Answer 16

reflective surface

Question 17

law which applies to all reflective surfaces

Answer 17

law of reflection

Question 18

what does the law of reflection state?

Answer 18

θ1 = θ2

Question 19

where should you measure angles from?
normal or surface

Answer 19

normal

Question 20

smooth surface, clean and sharp image

Answer 20

specular reflection

Question 21

uneven surface; no clear image, only light illumination

Answer 21

diffused reflection

Question 22

left of image is right of object, and vice versa

Answer 22

lateral reversal

Question 23

LOST stands for

Answer 23

L - location
O - orientation
S - size
T - type

Question 24

center of mirror surface

Answer 24

pole (P) or vertex (V)

Question 25

center of sphere

Answer 25

center of curvature (C)

Question 26

line passing through P and C

Answer 26

principal/outside axis

Question 27

distance PC

Answer 27

radius of curvature (R)

Question 28

point where reflected rays converge or appear to diverge

Answer 28

focus/focal point (F)

Question 29

distance FP

Answer 29

focal length (f)

Question 30

are images formed when an object is on the F? (concave mirrors)

Answer 30

NO

Question 31

converging mirror

Answer 31

concave

Question 32

diverging mirror

Answer 32

convex

Question 33

4 types of rays

Answer 33

1. parallel, through F 2. through F, parallel 3. vertex 4. to C

Question 34

transparent optical components designed to focus/diverge light; allow light to pass

Answer 34

lenses

Question 35

converging lens

Answer 35

convex

Question 36

diverging lens

Answer 36

concave

Question 37

thicker in middle; converges parallel rays; has focal points

Answer 37

convex lens

Question 38

thinner in middle; spreads light rays

Answer 38

concave lens