Topic 8 – Space Physics (Post 2018) Flashcards
(40 cards)
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
