Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physics > Cosmology > Flashcards

Cosmology Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What are the 3 Laws of Kepler?

A

The orbits are ellipses, equal areas are swept out in equal time intervals, T^2 is proportional to r^3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a satellite?

A

an object in orbit around another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

First three stages of a star forming?

A

Nebula - cloud of dust and gas, Protostar - critical temp. fusion starts, Main Sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Last three stages of a small star?

A

Red Giant - core collapse, shell burning, White Dwarf - layers drift off, hot core, Black Dwarf - cools, invisible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Last three stages of a massive star?

A

Red Supergiant - layers of fusion until core made of iron, Supernova, Neutron star/black hole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What holds a white dwarf together?

A

Electron degeneracy pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What holds main sequence star together?

A

Gravity inwards, gas and radiation pressure outwards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What holds a neutron star together?

A

Neutron degeneracy pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the Chandrasekar Limit?

A

The max mass that electron degeneracy pressure can prevent the collapse of - 1.44Mo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the event horizon?

A

boundary of black hole where the escape velocity is greater than the speed of light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the Schwarzchild radius?

A

The distance from the singularity of a black hole to the event horizon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is luminosity?

A

The total radiant power output of a star

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why are emission spectra better than absorption?

A

Some lines may be missing from the absorption spectrum because electrons may deexcite indirectly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do absorption spectra work?

A

Photons bombard electrons cooler gas, causing them to excite. The electrons deexcite, and scatter photons which do not reach the sensor, causing a black line spectrum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why are telescopes better than eyes?

A

wider aperture collects more light and is less similar to the wavelength of light = less diffraction = less image distortion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a black body?

A

a perfect emitter and absorbs all EM radiation

17
Q

What is the Stefan-Boltzmann law?

A

total power radiated per unit surface area of a black body is directly proportional to temperature^4

18
Q

How old is our universe?

A

Approx. 13.5 billion years

19
Q

Steady State Theory

A

Matter is created continuously

20
Q

How many light years is a parsec?

A

3.26

21
Q

What is 1AU?

A

1.5x10^15m

22
Q

What is a parsec?

A

The distance at which the radius of 1AU subtends the angle of an arcsecond.

23
Q

What is recessional velocity?

A

The speed at which a galaxy is moving away from another

24
Q

What is the cosmological principle?

A

universe is isotropic and homogeneous when viewed on a large scale

25
Q

What does isotropic mean?

A

universe looks the same in all directions, no centre or edge to it

26
Q

What does homogeneous mean?

A

matter is evenly distributed - no preferred location, density is constant

27
Q

What are the universal laws?

A

theories and models of physics tested on Earth can be applied to the whole universe

28
Q

What is the evidence supporting the Big Bang?

A

red shift shows galaxies are accelerating away, temperature and CMB matches expected cooling, 2.7K, spectrum matches a black body, relative abundance of light elements (H and He)

29
Q

How is CMB evidence for the Big Bang?

A

shows that when matter and radiation were strongly coupled, universe was isotropic and homogeneous, temp at 2.7K, expected

30
Q

Properties of CMB radiation?

A

isotropic, temp of 2.7K, black body spectrum

31
Q

How was CMB radiation formed?

A

Early universe hot, matter and radiation in thermal equilibrium,

Physics (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions