Topic 8 – Space Physics (Post 2018) Flashcards
Explain why the star is stable while it is in the main sequence stage of its life cycle
gravitational force inwards and forces as a result of fusion reactions outwards
are in equilibrium / balanced
Describe what will happen to the star between the main sequence stage and the end of the
star’s life cycle.
You should include the names of the stages in the life cycle of the star.
(the star will) expand to become a red giant
(the star will) collapse to become a white dwarf
allowed outer layers ejected for collapsed
(the star will) cool to become a black dwarf
The term red-shift describes the observed increase
in the ________________________________ of the light from a distant galaxy.
wavelength
How does the Big Bang theory describe the universe when it began?
(extremely) hot and dense
Describe the relationship between the speed of a galaxy and the distance the galaxy is
from the Earth.
(directly) proportional
whats the same as 6 x 10 ^12 terametres?
6 x 10 ^ 24 m
Explain how the data in the figure above supports the suggestion that the universe began
from a very small region.
the furthest galaxies are moving the fastest
(this suggests) the universe is expanding (from a very small region)
New observations suggest that distant galaxies are moving away from the Earth at an
increasingly fast rate.
What do the new observations suggest is happening to the universe?
expanding at (an ever) greater rate
New observations and data that do not fit existing theories should undergo peer review.
Give one reason why peer review is an important process.
- detects false claims
- detects inaccurate data
- detects bias
- verifies new data
*provides a consensus (of opinion)
The Andromeda galaxy is moving towards the Earth.
Describe how the wavelength and frequency of the light from Andromeda seem to have
changed when viewed from the Earth.
wavelength (seems to have) decreased
frequency (seems to have) increased
A satellite is in a circular orbit around the Earth
Explain why the velocity of the satellite changes as it orbits the Earth
(force of) gravity causes the satellite to accelerate (towards the Earth)
the acceleration causes a change in direction
velocity changes because direction changes
A satellite orbits 300 km above the Earth’s surface at a speed of 7.73 km/s.
Calculate how many complete orbits of the Earth the satellite will make in 24 hours.
42 100 = 7.73 × time
time (1 orbit) = 5446(s)
= 15.86
number of orbits = 1
The predicted data can be considered to be accurate.
Give the reason why.
the predicted data is very close to the actual data
J Bode used his equation to predict the existence of a planet with an orbital radius of 2940
million kilometres.
The planet Uranus was discovered in 1781.
Uranus has an orbital radius of 2875 million kilometres.
Explain why the discovery of Uranus was important.
supported the prediction (made by Bode)
so provides evidence that the equation is true / correct / works / accurate
Which one of the following types of electromagnetic wave has the highest frequency?
gamma rays
What makes microwaves suitable for sending communications to a satellite in space?
can travel through the atmosphere
What event leads to a neutron star forming?
explosion of a red super giant / a supernova
When radio waves are absorbed by an aerial they may create an alternating current in an
electrical circuit. If an alternating current is created what frequency would it have?
same as the radio wave
The Sun is in the group of main sequence stars. These stars are stable.
Explain why a star remains stable.
expansion due to fusion energy
in equilibrium with
At different points in their lifecycle stars change from one group to another.
Describe what will happen to the Sun between it leaving the main sequence group and
becoming a white dwarf.
* Sun goes from main sequence to red giant
* then from red giant to white dwarf
* when the Sun changes to a red giant the surface temperature
will decrease
* and the relative luminosity will increase
* when changing from a red giant to a white dwarf the surface
temperature increases
* and the relative luminosity decreases
What provides the force needed to keep a satellite in orbit around the Earth?
gravity
Explain how a current is induced in the wire.
as the wire moves through the Earth’s magnetic field
a potential difference is induced between the ends of the wire
the wire must be part of a complete circuit
Main sequence star -> Black dwarf is __
Main sequence star, Red giant, White dwarf, Black Dwarf
Only stars _____ as the sun become Black dwarfs
same/similar mass
In which stage of the life cycle of a star are elements heavier than iron produced?
supernova
When scientists observe the light from distant galaxies, they observe an increase in
the ____________of light from those galaxies.
wavelength
Write down the equation that links distance travelled (s), speed (v) and time (t).
distance = speed × time
Describe the life cycle of stars much more massive than the Sun, including the formation of
new elements.
* fusion (processes in stars) produce new elements
* cloud of gas / hydrogen and dust OR nebula
* pulled together by gravity
* causing increasing temperature (to start the fusion process)
* (to become a) protostar
* hydrogen nuclei fuse to form helium nuclei
* and the star becomes main sequence
* hydrogen begins to run out
* helium nuclei fuse to make heavier elements
* up to iron
* the star expands (to become a)
* red super giant
* (the star collapses rapidly) and explodes
* called a supernova
* creating elements heavier than iron
* and distributing them throughout the universe
* leaving behind a neutron star
* or a black hole.
Which property of a star does the range of wavelengths depend on?
temperature
How does the mean surface temperature of the planets in the table change as the mean
distance from the Sun increases?
it decreases
Why is the Moon classified as a satellite?
It orbits a planet.
How are planets and moons similar?
Their orbits are circular.
They do not emit visible light.
The Sun was formed when a ____________________ in space was pulled
together by ____________________
nebula gravity
What stage in the lifecycle of the Sun will follow the Main Sequence stage?
(becomes a) red giant
What pattern links the distance a planet is from the Sun and the time taken by the planet to
orbit the Sun?
the greater the distance (from the Sun) the greater the time taken to
orbit the Sun
‘The mean surface temperature of a planet decreases the
further the planet is from the Sun.’
Explain why this conclusion is not totally correct
because some planets do not fit the pattern
named planet that does not fit pattern
Describe the orbit of an artificial satellite.
circular
The star Mira will go through a supernova stage in its lifecycle but the Sun will not.
How is the star Mira different to the Sun?
Mira is much more massive
What relationship between the speed of a galaxy and the distance is suggested by
Hubble’s results?
the further away from the Earth, the faster a galaxy is moving
a student uses a balloon to model the idea of an expanding Universe.
Some dots, which represent galaxies, were marked on the balloon.
The balloon was then inflated.
Give one strength and one weakness of this model in representing the idea of an
expanding Universe.
strength:
as the balloon expands the dots get further apart, representing the galaxies moving apart
weakness:
dots are only on the surface of the balloon, galaxies are throughout the universe
