Light and Optics

Question 1

electromagnetic wave

Answer 1

traveling oscillation of an electric and magnetic field, fields perpendicular to each other, direction of propagation is perpendicular to both fields, transverse wave
produced by acceleration of charges

Question 2

c = ratio

Answer 2

c = E/B

Question 3

light

Answer 3

tiny sliver from electromagnetic spectrum

wavelengths from 390 x 10^-9 to 70 x 10^-9 m

Question 4

c =

Answer 4

frequency x wavelength

Question 5

index of refraction

Answer 5

compares speed c of light in a vacuum to speed v of light in a particular medium
n = c/v

Question 6

emission spectrum

Answer 6

spectroscope separates wavelengths via diffraction and refraction, fingerprint to identify any given element

Question 7

fluorescence

Answer 7

energy source bumps electrons up more than one energy level, excited e-s drop back down in smaller energy level steps releasing visible light

Question 8

plane-polarized light

Answer 8

screen out all photons not having an electric field in one particular direction, resulting light with all electric fields oriented in same direction
isotropic light loses one half its intensity

Question 9

lasers

Answer 9

light that is both spatially and temporally coherent can be forced into a parallel beam that spreads and weakens very little over great distances

Question 10

Snell’s Law

Answer 10

n1 sin(theta1) = n2 sin(theta2)

Question 11

when light crosses into a new medium….

Answer 11

the frequency remains the same and the wavelength changes

Question 12

energy of single photon =

Answer 12

E = hf
h= planck's constant

Question 13

critical angle

Answer 13

angle of incidence large enough to cause total internal reflection

Question 14

chromatic dispersion

Answer 14

white light is split by a prism, result of refraction, longer wavelength/lower frequency bend less

Question 15

diffuse reflection

Answer 15

when light ray strikes rough surface, parallel rays of lights reflect away at different directions

Question 16

diffraction

Answer 16

when a wave moves past the edge of an object, it bends around the object
all types of waves diffract, waves diffract around all objects

Question 17

diffraction: the smaller the opening and the larger the wavelength….

Answer 17

the greate r the bending of the wave

Question 18

X-ray diffraction

Answer 18

x-rays that are projected at a crystal scatter and create regular interference patterns unique to the structure of the crystal, used to analyze crystalline structure

Question 19

focal point

Answer 19

focal length = 1/2 radius of curvature,
concave mirrors and converging lenses: rays focus here
convex mirrors and diverging lenses: reflected and refracted outward from this point

Question 20

power of a lens

Answer 20

measured in diopters
units: m^-1
P = 1/focal length

Question 21

lateral magnification

Answer 21

ratio of the size of the image to the size of the object

m = -di/do = hi/ho

Question 22

angular magnification

Answer 22

angle of object when at the near point compared to angle occupied by image of the object when in front of a lens
m= theta_i/theta_np

Question 23

f, do, di relationship equation

Answer 23

1/f = 1/do + 1/di

thin lens equation

Question 24

Eye am positive that…

Answer 24

Eye am positive that real is inverted
observer side = +, real, inverted
other side = negative, virtual, upright

Question 25

convex mirrors and diverging lenses make…

Answer 25

negative, virtual, upright images

Question 26

concave mirrors and converging lenses make…

Answer 26

positive, real, inverted images except when object is within focal distance….then negative, virtual, upright

Question 27

lateral magnification of 2 lens system

Answer 27

M = m1*m2

Question 28

two lenses in contact effective power

Answer 28

P = P1 + P2