Brainscape's Knowledge GenomeTM

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


See full index

IGCSE PHYSICS MATS > 5) Astrophysics > Flashcards

5) Astrophysics Flashcards

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

What is the universe?

A
  • a large collection of billions of galaxies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a galaxy?

A
  • a large collection of billions of stars
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the name of our solar system?

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

What does the gravitational field strength of a planet depend on?

A
  • radius of planet

- density of planet

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

What is the relationship between mass and gravitational force?

A

gravitational force is directly proportional to the mass

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

What is the relationship between gravitational force and distance?

A

gravitational force is inversely proportional to the distance

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

As the distance increases, the gravitational force ___________

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

As the mass increases, the gravitational force ___________

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

What is the equation to find orbital speed (v)?

A 
v = 2πr/T
v = orbital speed (km/s)
r = orbital radius (km)
T = time period (seconds)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why does gravity cause things to orbit things (in general)

A
  • gravity pulls things to the ground

- gravity acts on all stars, planets, moons

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

When is GPE strongest?

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

What is a comet?

A
  • ball of dust and ice that travels through the solar system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What type of orbits do comets have?

A
  • elongated elliptical orbits
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why do comets have 2 tails?

A
  • gas tail - points directly away from the Sun due to ‘solar winds’ (electrically charged particles streaming out of the Sun) that push it back
  • dust tail - lags behind the gas tail
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the orbit of a comet referring to its GPE and KE:

A
  • KE is fastest when close to the Sun
  • GPE is lowest when close to the Sun
  • KE of comet decreases as gravitational pull decreases when comet is moving away from Sun
  • GPE increases as comet moves away from Sun
  • KE lowest when furthest from Sun
  • GPE highest when furthest from Sun
  • GPE decreases as comet moves towards Sun
  • KE increases as comet moves towards Sun as gravitational pull increases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How are stars classified?

A
  • according to their colour
17
Q

What is the order of star classification from highest temperature to lowest temperature? What is each of these classes temperature? What is each of these classes colour?

A 
O - more than 33,000 K - blue
B - 10,000 - 33,000 K - blue white
A - 7,500 - 10,000 K - white
F - 6,000 - 7,500 K - yellow white
G - 5,200 - 6,000 K - yellow
K - 3,700 - 5,200 K - orange
M - 2,000 - 3,700 K - red
18
Q

What is the life cycle of a star that has a similar mass to the Sun?

A
  • stellar nebula
  • main sequence star
  • red giant
  • white dwarf
  • black dwarf
19
Q

What is the life cycle of a star that has a greater mass than the Sun?

A
  • stellar nebula
  • main sequence
  • red super giant
  • supernova
  • neutron star
  • black hole
20
Q

What is a stellar nebula?

A
  • cloud of cold hydrogen gas and dust which is collapsing due to the pull of gravity
21
Q

What is main sequence star?

A
  • the star releases energy from the fusion of hydrogen to form helium
  • the forces are balanced
22
Q

How does a main sequence star become a red giant?

A
  • due to hydrogen shortage, the main sequence star becomes unstable
  • the outward forces decrease and the star begins to collapse
  • this brings additional hydrogen into a zone where the temperature and pressure are sufficient to cause fusion
  • the outer layers expand greatly and the star enters the red giant phase
23
Q

How does a red giant become a white dwarf?

A
  • helium starts to fuse to make heavier elements such as carbon and oxygen
  • eventually the star is no longer able to fuse helium and its core cools down
  • the star collapses into a white dwarf
24
Q

How does a white dwarf become a black dwarf?

A
  • the white dwarf starts to cool down and it will eventually become a dark cold star
25
Q

What happens in a red super giant?

A
  • temperature in the core is so high that helium nuclei fuse to form heavier elements
  • elements as heavy as iron are produced by fusion
26
Q

How does a red super giant become a supernova?

A
  • red super giant runs out of nuclear fuel
  • forces of gravity overcome the outwards pressure from the center of the star
  • rapid collapse heats the inside of the star to such high temperatures that there is a nuclear reaction
  • the star explodes like a cosmic nuclear bomb
  • elements heavier than iron are made
27
Q

How does a red super giant become a neutron star or a black hole?

A
  • red super giant runs out of nuclear fuel
  • forces of gravity overcome the outwards pressure from the center of the star
  • star collapses rapidly
  • great gravitational forces cause the center to collapse into a highly condensed form of matter
  • might be left as a neutron star made only of neutrons
  • collapse may be so complete that the star disappears and has become a black hole
  • black hole is so dense that nothing, including light, can escape from it

IGCSE PHYSICS MATS (7 decks)

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