spectroscopy

Question 1

Temperature measure

Answer 1

the internal energy of an object

Question 2

1st Law of Spectroscopy

Answer 2

A dense gas or solid produces a
continuous (blackbody) spectrum

Question 3

a blackbody

Answer 3

• is a perf ect absorber of light at all wavelengths.
• reradiates that energy at all wav elengths as it warms up
• is described just by its temperature

Question 4

The peak wavelength of a blackbody

Answer 4

depends inversely on its TEMPERATURE
Wiens law

Question 5

Consequence of Wien’ sLaw

Answer 5

Hotter objects are BLUER
Cooler objects are REDDER

Question 6

A star radiates like a blackbody. If its surface
temperature doubles, the w avelength of maximum
intensity w ill be ___ times the original w avelength

Answer 6

0.5

Question 7

The energy output by a blackbody

Answer 7

depends only on its TEMPERATURE

Question 8

Flux =

Answer 8

Power released per square meter [W/m2]

Question 9

Stefan-Boltzmann Law:

Answer 9

The f lux f rom a blackbody depends
strongly on temperature:
Definition:
Flux = Power released per square meter [W/m2]
 = Stef an-Boltzmann
constant

Question 10

Consequence of Stefan-Boltzmann Law:

Answer 10

Hotter objects are Brighter* at All Wavelengths

Question 11

Luminosity =

Answer 11

Total Power [Watts

Question 12

find luminosity

Answer 12

Luminosity = Total Power [Watts]
Use the total surface area of the
star to find the energy emitted by
the star each second

Question 13

The total power radiated (the luminosity)

Answer 13

depends on f lux and size

Question 14

We measure the amount of red light given off by a red -
hot blackbody. When the blackbody is heated until it
glows bluish-white, the amount of red light it gives of

Answer 14

increases

Question 15

Blackbody radiation is observed from three planets. A
peaks in the visible, B peaks in the infrared, and C peaks
in the radio.
Which planet is hottest

Answer 15

planet A

Question 16

Hydrogen:
The Simplest Atom

Answer 16

one proton, one electron

Question 17

Behav ior on atomic
scales is gov erned
by

Answer 17

quantum mechanics

Question 18

One rule of quantum mechanics

Answer 18

Electrons can only exist on orbits of specific energy.
* mov e between by emitting or absorbing photons

Question 19

2nd Law of Spectroscopy:

Answer 19

A hot, transparent gas produces
an emission spectrum
right emission lines.
* Darkness between the emission lines

Question 20

Larger Jump =

Answer 20

= More Energy = Bluer Wav elength

Question 21

Elements with more electrons have

Answer 21

more spectral lines

Question 22

Emission lines

Answer 22

Emission lines are used to identify atoms (and molecules)

Question 23

When an atom absorbs a photon

Answer 23

(li ght-w ave),
an electron moves from a lower energy level
to a higher energy level

Question 24

3rd Law of Spectroscopy

Answer 24

A transparent gas, in front of a
hotter blackbody, produces an absorption spectrum.

Question 25

Absorption Lines

Answer 25

produced when electron absorbs a photon with exactly the
energy needed to jump f rom a lower to a higher orbital

Question 26

All stars produce dark line absorption spectra

Answer 26

Hot dense core,
surrounded by a low-
density outer atmosphere

Question 27

A spectral emission line results from

Answer 27

electrons j umping to a low er orbit