MIRRORS/OPTICS

law of reflection

incident/reflected ray + normal in same plane

angle incidence = angle reflection

describe rays in specular reflection

reflected rays parallel to eo

virtual image

none of rays emanate from image, behind mirror

concave mirror

inside surface of spherical mirror polished

convex mirror

outside surface of spherical mirror polished

principal axis

straight line thru center and midpoint of mirror

where are lightrays near + parallel to principal axis reflected

from concave mirror, converge at focal point. f = r/2 (R = RADIUS OF CURVATURE OF MIRROR)

focal length

distance between focal point and mirror

describe image produced by object between focal point and concave mirror

(real/virtual, size, upright/inverted)

enlarged, upright, virtual

virtual image produced by convex mirrors

reduced, upright

speed of light in vacuum

3 x 10^8

how does light travel thru materials vs. in vacuum

material is slower

index of refraction definition

ratio of speed of light in vacuum/in material. n = c/v

how does refracted ray bend away from normal

light passing thru medium of larger refractive index gets into one of smaller

A diverging/concave lens always forms

(real/virtual, size, upright/inverted)

an upright, virtual, diminished image.

image formation by convex mirror is always
(real/virtual, size, upright/inverted)

virtual, diminished, upright

what do rays do when paraxial lightrays strike convex mirror

• paraxial → alongside axis

• lightrays → parallel to axis

• 💡 (where do they originate + formula)

diverge/reflect outward, however, originate from focal point.

f = -R/2

variable representation: f, d0, di, m

focal length, object distance, image distance, magnification

sign conventions for lenses

convex = converging

concave = diverging

lens vs. mirror

• mirror bounces light off surface (reflection)

• lens allows light to pass through it, bending the light in the process (refraction)

sign conventions for mirrors

object in front = real

object behind mirror = virtual

snell law refraction

image characteristics of concave mirror

• between mirror and focal point

• between C (radius curvature) and focal point

  

concave vs. convex mirror and lens visual + formulas

mirror: +

lens: -

image characteristics of converging/convex lens

• between lens and F

• between F and 2F

• farther than 2F

3 properties of your image in the mirror

1. upright

2. same size

3. image as far behind mirror as u are in front

critical angle formula

mirror equations (magnification and 1/f)

for lens, 1/f = is - (Minus)

angle of incidence equals =

angle of reflection

mnemonic for images

UV IR

upright = virtual

inverted = real