Waves

Question 1

Wavelength

Answer 1

distance from peak to peak, measure in nanometers for light, Lamnda

Question 2

Frequency

Answer 2

How many complete wave lengths pass a point in one second, f, each cycle = 1 Hertz (Hz)

Question 3

Velocity of a Wave

Answer 3

v = frequency x wavelength, speed of wave, m/s

Question 4

White Light

Answer 4

Mixture of all colors of the spectrum in equal measures

Question 5

Blue light

Answer 5

400 nm, shortest

Question 6

Red light

Answer 6

750 nm, longest

Question 7

Wave nature of light

Answer 7

Light waves can interfere with each other

Question 8

Particle nature of light

Answer 8

Photons (Particles of light)

Question 9

Photons

Answer 9

Packets of electromagnetic energy, E=Frequency x Planck’s constant (h), energy carried by photon is proportional to its frequency (Blue carries more energy than red)

Question 10

Emission Spectrum

Answer 10

Distinct pattern of colored lines for each element, fingerprint for element since each is unique

Question 11

Bohr Atom

Answer 11

Electrons travel in specific cirular orbits around the nucleus, each orbit corresponds to a fixed energy level, electron can jump between orbits by absorbing or emitting energy in the form of light, F= change in energy/ h

Question 12

Bohr Atom Transitions

Answer 12

Level 3 to Level 1 transitions are more energetic than level 3 to level 2, Collection of all possible transitions produces an emission spectrum

Question 13

Electromagnetic Spectrum

Answer 13

Huge range of light, not all visible,
ORDER: radio wave, microwaves, infrared, visible light, UV, x-rays, Gamma Rays

Question 14

Radio Waves

Answer 14

Longest waves, 1mm-100km, used in radio, TV, cell phone communications, can travel long distances and through obsticles

Question 15

Microwaves

Answer 15

1mm-1m, used in food making, satellite communication and radar, get absorbed by water molecules

Question 16

Infrared (IR)

Answer 16

700nm-1mm, feel as heat, used in remotes, thermal imaging, and night vision glasses

Question 17

Visible Light

Answer 17

400nm - 700nm, only EM radiation our eyes can detect, colors

Question 18

Ultraviolet (UV)

Answer 18

10nm-400nm,, more energetic and harmful in large doses, sterilizes medical equipment, glows in black light

Question 19

X - Rays

Answer 19

0.01nm-10nm, can pass through most materials, medical imaging

Question 20

Gamma Rays

Answer 20

<0.01nm, most energetic, used in cancer treatment and nuclear reactions

Question 21

Kirchoff’s Laws

Answer 21

Describe how light interacts with different types of matter

Question 22

Kirchoff’s 1st Law

Answer 22

A hot, dense gas emits a continuous spectrum when heated

Question 23

Kirchoff’s 2nd Law

Answer 23

A hot, low density gas emits a discreet spectrum

Question 24

Kirchoff’s 3rd Law

Answer 24

When light of a continuous spectrum passes through a cool gas, it absorbs light at the same wavelengths that it would emit, these appear as dark lines in the spectrum (Absorption Spectrum)

Question 25

Absorption Spectrum

Answer 25

Helps us tell what a star is made of

Question 26

Transmission Spectoscophy

Answer 26

Star's light passes through a planet's atmosphere before reaching earth, certain wavelengths are absorbed by the planet's gases, gives us the chemical composition of the planet's atmosphere

Question 27

Viens Law

Answer 27

Hotter Objects have their peak emission at shorter wavelengths (blue) and cooler objects have their peak wavelength at longer wavelengths (red)

Question 28

Peak Wavelength

Answer 28

Where the radiation is the most intense, gives us the color we see, depends on the objects temp.

Question 29

Wien's Law

Answer 29

Used to find temp. of star if you know the peak wavelength Wavelength Peak = 2,900,000/ Temp.(in K)

Question 30

Color range of stars

Answer 30

From hottest to coldest Blue, Blue-White, Yellow, Orange, Red

Question 31

Doppler Effect

Answer 31

Change in the frequency or pitch of a sound as the source moves relative to the observer

Question 32

Waves get bunched

Answer 32

Higher frequency, pitch, in the direction the sound is moving towards

Question 33

Waves get stretched

Answer 33

Lower pitch as the object moves away

Question 34

Blue Shift

Answer 34

Star is moving towards earth, has condensed wavelengths causing emission spectrum to lean towards blue

Question 35

Red Shift

Answer 35

Star is moving away from earth, has spread out wavelengths causing emission spectrum to lean towards red

Question 36

Shift Equation

Answer 36

If change in wavelength is < 0 blue shift If change in wavelength is > 0 red shift

Question 37

Longer wave =

Answer 37

Higher Frequency

Question 38

Which photon has more energy red or green?

Answer 38

Green, higher frequency