Physics Space

Question 1

The sun is the only star in the

Answer 1

solar system

Question 2

There are how many planets in our solar system

Answer 2

8

Question 3

What type of celestial body is a moon?

Answer 3

natural satellite

Question 4

Formation of the sun steps

Answer 4

1. Cloud of gas and dust (a nebula) collapsed due to gravity
2. This formed a protostar which continued to accumulate more mass
3. The temperature and pressure became high enough for nuclear fusion to start
4. The star then went into a stable period called a main sequence star

Question 5

In the Sun, what process creates a force outwards, balancing the inward force of gravity?

Answer 5

Nuclear fusion

Question 6

The Sun is
currently ————–
and is powered by nuclear ———–
and is a ———– ————– star

Answer 6

stable
fusion
main sequence

Question 7

weight with units equations =

Answer 7

weight in newtons
mass (kg) * gravitational field strength N/kg

Question 8

comets and asteroids are balls of
which orbit the

Answer 8

ice and rock which also orbit the sun

Question 9

If the speed of the object in orbit changes then the

Answer 9

the radius of the orbit also changes.

Question 10

If the radius of the orbit increases then the

This explains why planets closer to the sun travel at a faster speed.

Answer 10

the speed decreases as the gravitational attraction is smaller.

Question 11

What happens when the radius of an object in orbit decreases?

Answer 11

speed increases

Question 12

What happens when the radius of an object in orbit decreases?

Answer 12

it speeds up

Question 13

In a main sequence star, ——————are fused together to form ——.
This releases energy as ——-and ——.

Answer 13

hydrogen nuclei
heluim

heat
light

Question 14

Red giant formation

Answer 14

Eventually all the hydrogen fuel runs out.
The star then cools and expands, becoming a red giant.
The star then starts to fuse together helium nuclei to release energy.
It is formed when he outward force of the energy is larger than the inward force of gravity so the star expands.

Question 15

White dwarf process

Answer 15

As the heluim fuel runs out in a small to meduim star like the sun then the, the outward forces reduce in size and the star collapses inwards ejecting its outer layer of gas and dust.
This causes is temperatures to increase. A white dwarf is formed which is the hot core of the star.

Question 16

Black dwarf very short summary

Answer 16

when the stars completely cools it becomes a black dwarf.
A black dwarf doesn’t emit any light or heat

Question 17

How does a star become a super red giant quick summary

Answer 17

Nuclear fusion changes more and more of the star’s mass into energy. The star expands into a red super giant

Question 18

Supernova quick summary (about how its created) what does it produce?

Answer 18

the largest stars explode into supernovas. A supernova produces elements heavy than iron and scatters them throughout the universe.

Question 19

Black holes and neutrons stars are formed

Answer 19

by a supernova

Question 20

Life Cycle of a large star

Answer 20

1. Gravitational attration pulls dust and gas together to form a protostar. As the density increases the temp rises. When the temp gets high enough nuclear fusion happens and a huge amount of energy is emitted
2. Main sequence star formed powered by nuclear fusion the star enters a long stbale priod where outward pressure ccaused by the nuclear fusion balances the forces of gravity pulling everything inwards. So the forces are balanced so it doesn’t collapse or explode. This typically lasts several billion years.
3. The star expands becoming a super red giant
4. The star explodes into a supernova
5. The supernova leaves behind either a black hole or a neutron star

Question 21

All stars fuse ——– nuclei into ——- in nuclear ———

Answer 21

hydrogen
helium
fusion

Question 22

Larger stars fuse —— nuclei into ——- and other ———

Answer 22

heluim
lithium
of light metals

Question 23

Describe red shift and explain how it supports the big bang theory as an explanation for how the universe began
(6 marker)

Answer 23

Red shift is when the wavelengths of observed light from a source are longer than that of the light emitted from the source. This occurs when the source of the light emitted by the source is moving away from the observer.

The light from the most distant galaxies is observed to be red-shifted. The light from galaxies that are further away from us is more redshifted than the light from nearer galaxies. This inidcates that all of these glaxies are moving away fromand each other. This suggests that the universe is expanding. The Big Bang theory is the theory that the universe began as a small region of space that was very hot and dense which exploded and his been expanding ever since. Therefore the observations of red-shift support the idea of the origin of the universe suggested by the BIG BANG THEORY

Question 24

Evidence for an expanding universe

Answer 24

Light from distant galaxies in space is red-shifted. The further a galaxy is from earth, the Greater the red shift. This means that the further away a galaxy is, the faster it is moving away from us.

Question 25

define dark matter

Answer 25

an unknown substance that holds galaxies together but doesn’t emit electromagnetic light radiation

Question 26

define dark energy

Answer 26

the thing that causes the universe to quickly expand

Question 27

Neumonic:

Answer 27

My Mercury
Very Venus
Easy Earth
Method Mars
Just Jupiter
Speeds Saturn
Up Uranus
Naming Neptune

Question 28

The doppler effect causes the wavelength of light from galaxies moving away from us

Answer 28

to increase in length . This moves the position of absorption lines towards the red end of the spectrum, so it is called red-shift.

Question 29

LEO Sattelite

Answer 29

LOwer
earth
orbit
Used for communication (orbit is about 90 minutes, gives detailed images of Earth)

Question 30

Black holes are

Answer 30

a super dense point in space that not even ligh can escape from

Question 31

neutron star is a

Answer 31

very dense core

Question 32

If an object is continually moving around a circle (orbiting) then it is constantly changing ————- but not

Answer 32

velocity
speed

Question 33

Observations of supernovae from 1998 to present day seem to suggest that

Answer 33

that distant galaxies are moving away from us faster and faster

Question 34

Describe what happens to stars after their red giant phase until the end of their lifecyle (3 marker)

Answer 34

they become unstable and eject their outer layer of dust and gases

which leaves behind a hot dense sold core known as a white dwarf

White dwarfs then cool to become black dwarfs

Question 35

Describe what happens to stars after their super red giant phase until the end of their lifecyle (3 marker)

Answer 35

They start to glow brightly again, undergo more fusion, and expand and contract several times

Heavier elements are formed and the star eventualy explodes into a supernova

The supernova leaves behind a neutron star or a black hole

Question 36

Explain why the velocity of the satellite changes as it orbits earth

Answer 36

(force of) gravity causes the satellite to accelerate (towards the Earth)
the acceleration causes a change in direction
velocity changes because direction changes

Question 37

Giga

Answer 37

10 to the 9

Question 38

mega

Answer 38

10 to the 6

Question 39

tera

Answer 39

10 to the 12