P16 - Space

Question 1

define:

nebula

Answer 1

a cloud of dust and gas

Question 2

describe:

forces acting on a main sequence star

Answer 2

force of gravity inwards and force of fusion outwards in equillibrium

Question 3

explain:

how fusion occurs inside a newly forming star

Answer 3

dust and gas drawn together due to gravity which causes heat to build up, causing nuclear fusion

Question 4

define:

centripetal force

Answer 4

an inwards force on an object which is moving in a circular path

Question 5

define:

centrifugal force

Answer 5

a ficticious force which seems to act outwards on an object moving in a circular path

Question 6

define:

doppler effect

Answer 6

change in wavelength due to change in distance to an observer

Question 7

define:

red-shift

Answer 7

emission spectra moved to the red end of the spectrum due to the doppler effect

Question 8

explain:

proof of the Big Bang theory

Answer 8

1. red-shift viewed in stars
2. most are moving away
3. universe is expanding

Question 9

describe:

life of a star

size of the sun or smaller

Answer 9

nebula → protostar → main sequence star
→ red giant → white dwarf → black dwarf

image

Question 10

describe:

life of a star

larger than the sun

Answer 10

nebula → protostar → main sequence star
→ red super giant → supernova → neutron star / black hole

image

Question 11

define:

light year

Answer 11

distance that light travels in one year

Question 12

define:

universe

Answer 12

all matter and energy that exists

Question 13

list 2:

orbits

Answer 13

low polar orbit
geostationary orbit

Question 14

name 1:

use of a low polar oribt satellite

Answer 14

• Earth surface imaging
• military (espionage)
• weather monitoring

Question 15

name 1:

use of a geostationary orbit satellite

Answer 15

• GPS
• telecommunications