Topic 1-4 Main Knowledge

Question 1

What is EMR?

Answer 1

1. EMR is created whenever a charge is accelerated, the acceleration of a charge creates a pulse changing electric and magnetic fields

Question 2

who created the first mathematical electromagnetic wave theory?

Answer 2

james clerk maxwell

Question 3

JC Maxwell predicted that EMR should be created when….

Answer 3

an electric charge is accelerated/oscillated

Question 4

ROYGBIV

Answer 4

red
orange
yellow
green
indigo
violet

Question 5

most accurate way to measure speed of light

Answer 5

michelson; using a rotating mirror and a fixed mirror separated by a large distance. A light source projects light onto a rotating mirror. The reflected light then travels to the fixed mirror and back again. The time is measured by the rotation of the mirror

Question 6

reflection wave

Answer 6

when a wave is directed back into the medium after hitting the boundary to another medium

Question 7

law of reflection

Answer 7

where angle of reflection is equal to angle of incidence

Question 8

refraction

Answer 8

bending of light due to light changing speed as it goes from one medium to another

Question 9

high index to low index

Answer 9

light bends away from normal

Question 10

low index to high index

Answer 10

light bends towards normal

Question 11

total internal reflection

Answer 11

waves arriving at the interface/boundary from one medium to another (e.g., from water to air) are not refracted into the second (“external”) medium, but completely reflected back into the first (“internal”) medium.

Question 12

Mirrors are either classified as

Answer 12

concave or convex

Question 13

a concave mirror

Answer 13

reflects parallel ray inward the principal axis and the focus

Question 14

a convex mirror

Answer 14

reflects parallel rays outward away from the principal axis and focus

Question 15

a ray that is parallel to the principal axis will be

Answer 15

reflected toward or away from the focal point

Question 16

a ray going through the focal point or toward the will focal point will

Answer 16

be reflected parallel to the principal axis

Question 17

real image

Answer 17

one that is formed on the side where the eye is placed for viewing, formed by “real” light rays —> can be projected onto a screen and are upside down

Question 18

virtual image

Answer 18

is on the opposite side to your eye, these are formed by “virtual” light rays —-> cannot be projected onto a screen and appear upright

Question 19

lens can be classified as either

Answer 19

converging or diverging

Question 20

converging lens

Answer 20

aka convex lens, refracts parallel rays inward toward the principal axis and focus

Question 21

diverging lens

Answer 21

aka concave lens refracts parallel rays outward away from the principal axis and the focus

Question 22

distance in thin lens equation

Answer 22

• real focal points or images = positive
• virtual focal points or images = negative

Question 23

height in thin lens equation

Answer 23

• upright images = positive
• inverted images = negative

Question 24

The 7 wavelength EMR waves

Answer 24

radio = 10^3 and F:10^4
Microwave = 10^-2 and F: 10^8
infrared = 10^-5 and F: 10^12
visible = .5 x 10^-6 and F: 10^15
ultraviolet = 10^-8 and F:10^16
x ray =10^-10 and F: 10^18
gamma ray = 10^-12 and F: 10^20