astrophysics

Question 1

suggest why the speed of the comet changes

Answer 1

• transfer of GPE to KE

Question 2

name of force that causes the comment to orbit the sun

Answer 2

• gravational force

Question 3

define these terms:
universe
galaxy
solar system
moon
star

Answer 3

• large collection of billions galxies
• large collection of billions of stars
• collection of planets orbiting a common star
• naturals satelities that orbit a planet
• ball of hydrogen + helium giving out light/heat from nuclear fusion

Question 4

State one way in which the orbits of earth and mars are different

Answer 4

• different orbital Radii

Question 5

Evolution of a star much bigger than the sun

Answer 5

Nebula
Protostar
Main Sequence Star (fuses hydrogen)
Red SuperGiant (runs out of hydrogen and fuses larger elements to iron)
Supernova (can’t fuse any more and gravity causes the star to collapse)
Neutron Star or Black Hole

Question 6

Colours of Stars

Answer 6

Hot Stars = White / Blue

Cold Stars = Red

Question 7

Evolution of the sun

Answer 7

1. Nebula
2. Protostar
3. Main Sequence Star (fusing hydrogen)
4. Red Giant (star has run out of hydrogen and fusing helium)
5. White Dwarf (no more fusion)
6. Black Dwarf (white dwarf cools into a black dwarf)

Question 8

main sequence star

Answer 8

• fuses hydrogen nucleui

- in the core of star

Question 9

describe how star is formed from a nebula

Answer 9

• Gas particles inside the nebula attract OR collapse due to gravity
• KE/ speed of particles increases = temp increases
• hot + dense enough —> nuclear fusion starts