17 Astronomy

Question 1

Sun

Answer 1

Star that produces its own light

Question 2

Shape of the orbits path of the planet

Answer 2

Elliptical

Question 3

4 planets nearest the Sun

Answer 3

rocky and small

Question 4

4 planets furthest from the Sun

Answer 4

gaseous and large

Question 5

Composition of Sun

Answer 5

Hydrogen and Helium

Question 6

average orbital speed

Answer 6

πr² / t

Question 7

Galaxy

Answer 7

Consist of billions of stars

Question 8

Galaxy that the Sun located

Answer 8

Milky Way

Question 9

1 light year

Answer 9

distance that light travel in one year
: 9.46x10^15
(3 x 10^8) x 365 x 24 x 60 x 60

Question 10

Nebula

Answer 10

Cloud of dust and gas pulled together by gravity

Question 11

Protostar

Answer 11

GPE converts to thermal energy
temperature rises

Question 12

Stable star (Main sequence star)

Answer 12

Outward : force due to high temperature in centre of star
Inward : force due to gravity

Question 13

Red giant

Answer 13

Hydrogen begins to run out
red = surface is cool

Question 14

Planetary Nebula

Answer 14

Small + medium size star = unstable + eject its outer layer

Question 15

White draft

Answer 15

inner part = hot and dense solid core which will eventually disappear

Question 16

Red supergiant

Answer 16

Big stars undergo fusion and expand
As fusion fuel is running out the star contract

Question 17

Supernova

Answer 17

Red supergiant explode

Question 18

Neutron star

Answer 18

the exploding leaves a very dense core

Question 19

Black hole

Answer 19

the star is big enough to form a black hole

Question 20

Red shift

Answer 20

Light from distance galaxies have lower frequency than it should be

Question 21

Hubble constant

Answer 21

v = H0d
: ratio of speed of recession to distance away from observer

Question 22

Equation age of universe

Answer 22

1 / H0

Question 23

Motion of the distant galaxy

Answer 23

Distant galaxy is moving away from Earth

Question 24

Red shift

Answer 24

Observed light have lower frequency or higher wavelength

Question 25

Cosmic microwave background radiation (CMBR)

Answer 25

Electromagnetic radiation which occurs every part of universe and has wavelength in range of microwave

Question 26

Theory that uses red shift and CMBR as evidence

Answer 26

Big bang theory