Chapter 5 Flashcards
Order of waves (left to right)
gamma rays, x-rays, ultraviolet, infrared, radio.
all light… (speed)
travels at same speed (300,000 km/s.)
what is wavelength?
the distance between adjacent peaks of the electric (and magnetic) field.
longer wavelength =
lower frequency
shorter frequency =
higher frequency which is dangerous
higher frequency equals
higher energy
c = (equation)
3.0 x 10^8 m/s
Atomic number =
of protons
Atomic Mass Number =
of protons + neutrons
the nucleus is 100,000 times smaller…
but contains all masses
Nucleus contains…
protons(red) and neutral neutrons (grey)
isotopes :
same # of protons but different # of neutrons (4He, 3He)
Molecules:
consists of two or more atoms (h2o, CO2)
how do light and matter interact?
emission
absorption
transmission
reflection or scattering
Emission means
to emit light
Absorption means
to absorb light
Transmission means
to pass light
why is a rose red?
it reflects red light
each type of atom has a ?
unique set of energy levels
each transition corresponds to..
a unique photon energy, frequency, and wavelength
when do energy levels for electrons vary? (hydrogen)
from one element to another
Downward _________ produce a unique pattern of ________ lines. (Emits a ______ of a specific ______)
transitions, emission
Photon, frequency
Lower than red
Infrared. Slow movements
Upward transitions produce
A pattern of ABSORPTION lines at the same WAVELENGTH
From level 1 to level 2 it needs…
Ultraviolet
Amount of nm that can send electron from level 2 to level 4?
486.1 nm
Hotter objects emit
More light
Hotter objects have
Higher average energy
Why is Betelgeuse red?
It’s surface is cooler than that of the sun
How do we generally measure the Doppler Effect?
From shifts in the wavelengths of spectral lines
Doppler shift tells us only about the part of
An objects motion toward or away from us
Rotating planet
Gives both red and blue shifted lines
How do telescopes help us learn about the universe?
- Telescopes collect more light than our eyes
- telescopes can see more detailed than our eyes
More light than our eyes ➡️
Light collecting area
More detail than our eyes ➡️
Angular resolution
Largest Optical Telescope?
10.4m - Gran Telescopio Canarias (2007)
2nd largest optical telescope?
10.2m - South African Large Telescope (2005)
3rd largest optical telescope?
10m keck 1, Keck 2 (1993/1996)
Diameter of Radio telescope in Puerto Rico?
305 meters
Cons of Radio Telescope?
Very limited view, could only see in zenith
What emits X-Rays!?
Million degree gas
What does the first set of nested mirrors do?
Deflects X-rays to the second set
What does the 2nd set do?
Deflects X-rays a second time to the focus point
1st reason why we put telescopes into space?
Light pollution (avoid light from human sources)
2nd reason why we place telescopes in space
Turbulence causes twinkling which Blurs Images (turbulence is in earths atmosphere)
3rd reasons why we put telescopes in space?
Atmosphere absorbs most of EM spectrum, including all UV and Xray and most infrared.
What is interferometry?
A technique that allows two or more telescopes to work together TO OBTAIN THE ANGULAR RESOLUTION of a large telescope
which is hottest?
A) blue star
B) red star
C) planet that emits only infrared light
A) blue star
Blue stars are hotter than red
