topic 8 space

Question 1

which galaxy is our solar system part of

Answer 1

the milky way

Question 2

what type of force pulled together the cold of dust and gas to form the sun

Answer 2

gravitational force of attraction

Question 3

what word is used to describe a could of dust and gas

Answer 3

a nebula

Question 4

what type of reaction takes place when dust and gas is drawn together

Answer 4

fusion reactions

Question 5

what factor determines the type of lifecycle a star undergoes

Answer 5

size of star

Question 6

which two phases do all stars undergo

Answer 6

protostar phase

main sequence phase

Question 7

what is the protostar phase

Answer 7

when all cloud and dust are pulled together with the gravitational force of attraction

Question 8

what is the main sequence star

Answer 8

when the outward pressure caused by the nuclear fusion is the same as the force of gravity pulling everything inwards

Question 9

what two thing can star much bigger than the sun become at the end of their life cycle

Answer 9

neutron star

black hole

Question 10

what conditions are required for fusion reactions to occur in a star

Answer 10

very high temperatures

Question 11

how are elements heavier than iron produced

Answer 11

in a supernova

Question 12

what fuses together to form heavier elements in a star

Answer 12

hydrogen nuclei fuse to form heavier elements

Question 13

how are elements distributed throughout the universe

Answer 13

through the explosion of a massive star

Question 14

what allows planets and satellites to maintain circular orbits

Answer 14

gravity provides the gravitational force that acts as the objects centripetal force

the presence of centripetal force allows for the object to maintain its circular orbit

Question 15

what type of satellite can a planets moon be described as

Answer 15

a natural satellite

Question 16

give two examples of artificial satellites

Answer 16

tv satellites

satellites used for satellite imaging

Question 17

explain why for a stable orbit, the radius of orbit must change if the speed changes

Answer 17

at higher speeds, the object requires a greater centripetal force

for greater centripetal force the gravitational force must increase

this is achieved by the radius of the orbit being reduced

Question 18

explain how the force of gravity acting on a satellite affects its speed and velocity

Answer 18

the force can altar its velocity since the direction is continually changing

it cant cause a change of speed since there is no force component in the direction of motion

Question 19

what is red shift

Answer 19

an observed increase in the wavelength of light from distant galaxies

Question 20

what two things can be said about the motion and wavelength of emitted light from a galaxy, the further away it is?

Answer 20

the further the galaxy the faster its moving

the further away the galaxy is the greater the observed increase in wavelength

Question 21

what does redshift provide evidence for

Answer 21

provides that the universe is still expanding

supports big bang theory

Question 22

what does big bang suggest

Answer 22

the entire universe started from a very hot and dense region in space

Question 23

what can you say about redshift and movement when a galaxy is far away

Answer 23

galaxy further away is travelling faster

observed red shift is greater the further it is