Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Solar System Cosmos > Idk > Flashcards

Idk Flashcards

1
Q

What is ellipticity vs eccentricity

A

Both represent shape of ellipse but ELL is easier to relate to axes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is keppler’s first law

A

orbit of each planet is an ellipse, with the sun at one focus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the perihelion

A

the focal point of an ellipse where the sun is (so imagine travels faster near perihelion)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is kepler’s second law

A

as a planet orbits, it sweeps out equal areas in equal times (faster closer to the sun therefore)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is kepler’s third law

A

further away, slower speeds. p^2 = a^3. (p is orbital period in years and a^3 is the average distance from the sun)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is galileo’s theory of relativity

A

an object falling is constantly accelerated, free motion is at constant speed and direction, and there is no way to tell if a “vehicle” is in constant motion (like only feeling acceleration in a train, not speed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is momentum

A

mass * velocity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

newtons 3 laws

A

1: object moves at constant velocity except when acted upon by a force
2: F = ma
3: equal and opposite forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

newtons 3 laws

A

1: object moves at constant velocity except when acted upon by a force
2: F = ma
3: equal and opposite forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what conservation laws are there

A

mass energy equivalence
momentum
angular momentum
energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

emmy noether’s contribution

A

basically said that every property of a physical system which is smooth and continuous, has a conservation law corresponding with it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

three main types of energy

A

kinetic, radiative (light), potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

difference between temp and thermal energy

A

temp is average kinetic energy of particles in an object, whereas the thermal energy is total kinetic energy of the particles in an object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

newtons universal law of gravitation

A

every mass attracts every other mass,
attraction is proportional to the product of masses, and inversely proportional to distance between them squared

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

centre of mass relevance to orbits

A

both objects in an orbit, rotate around the centre of their two masses (like a balance point). it is only noticeable when masses are comparable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what does newtons adaption of kepler III allow us to do

A

allows us to weigh distance object by observing the period and measuring the separation of the two objects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how does gravity cause tides

A

the gravity pulls on the close side of the water more than the earth (as gravity acts on the centre of earth), making the bulge closest to moon, and also acts less upon the far side of water, therefore making bulge on opposite side of earth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

explain tidal friction

A

the movement of the tide opposes the spinning of the earth, causing a tidal friction which slows the earths rotation, and makes the moon spin faster, but further from the earth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

why is a day 23 hours 56 minutes not 24 hours like 1 full rotation

A

because by the time the earth has fully rotated, it has moved in its orbit around the sun, and therefore the sun appears in the same spot earlier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what might effect the spin of the earth

A

ice caps melting means more free moving water rather than rigid moving. maybe centre of earth spinning differently

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

order of planets in solar system

A

mercury, venus, earth, mars, jupiter, saturn, uranus, neptune

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

describe mercury

A

closest to the sun, made of metal and rock, with a large iron core. cratered, with long steep cliffs. slow rotation, meaning hot side and cold side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

describe venus

A

second planet from sun, similar size to earth. surface hidden by clouds, extreme greenhouse effect (way too hot).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

ndescribe mars

A

not much atmosphere, liquid water flowed in past, but not anymore.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

describe jupiter

A

much further out than previous planet, mostly hydrogen and helium, no solid surface. rings and many moons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

describe saturn

A

giant and gaseous, with non-solid rings made of ice and rock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

describe uranus

A

made of helium and hydrogen compounds, extreme axis tilt (spins toward sun)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

density of water (told is assumed knowledge and to memorise)

A

1 g/cm^3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

terrestrial vs jovian planets

A

inner 4 planets are closer to the sun, smaller and rocky (terrestrial)

outer 4 planets are further from the sun, larger and gaseous (jovian)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

how do you measure the distance to venus from earth

A

measure from 2 spots on earth looking at the sun past venus, use trig and triangles to see distance from distance between points on earth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what is nebular theory

A

the solar system formed from the gravitational collapse of a giant interstellar gas cloud - the solar nebula

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what is galactic recycling

A

the concept that gas clouds condense to form stars which form new elements, and then explode, forming new gas clouds and it is all recycled

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

how does a star collapse

A

it collapses down its smallest axis first, and then down its larger axis. therefore as it collapses, its angular momentum is conserved, making it spin faster. it also loses gravitational potential energy (making it hotter, forming the properties we know as a star.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what are orbiting disks in newly formed stars

A

collisions between particles form the clouds into a disk, with the heat and mass concentrated in the centre. this forms observable disks around the star in the middle which are what forms planets.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

why are the two types of planets (terrestrial and jovian) formed

A

the centre of the disks around stars is hotter than the outer, meaning most gaseous materials that were not accreted (accumulated) by planets are blown away by solar wind, to further planets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

how did terrestrial planets form

A

inside the frost line (where ice could not exist), small particles of rock and metal collided and built up into planetesimals, which eventually assembled into terrestrial planets.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

where did jovian planets come from

A

outside the frost line, ice could form small particles, allowing larger planetesimals and planets to form, where they drew in H and He gas through a process called accretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

why has the sun’s rotation slowed

A

likely the friction between solar magnetic field and solar winds over time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

difference between asteroids and comets

A

they are both left over junk from accretion process, but asteroids are rocky and inside the frost line, and comets are icy and outside the frost line

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

how might water have come to earth (3 explanations)

A

comets and asteroids carry trapped water, the rocks forming earth carried it originally and then it escaped from inside earth, or hydrogen in the atmosphere reacted to form water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

how does dating of rocks work

A

all elements of a rock formed at the same time. therefore if radioactive isotopes discovered, the known half-life is used to find age as they count parent and daughter atoms (basically how much has decayed)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

how can we tell the different layers of terrestrial planets

A

by looking at the velocities of longitudinal and transversal waves though the earth (by firing them through different areas), we can differentiate what makes up different layers. the transverse wave cannot go through the crust, but the longitudinal can.

43
Q

why is the earths core hot?

A

accretion and differentiation when planets were young, the loss of potential energy as it condensed into kinetic energy, and now it’s more due to radioactive decay

44
Q

how does a planets interior cool?

A

convection (hot materials rise, cool falls), conduction (transfers heat directly between material), radiation (sends energy into space)

45
Q

why do planets have magnetic fields (three requirements)

A
  • molten electrically conducting interior
  • convection
  • moderately rapid rotation
46
Q

which processes shape the surface of planets

A

impact cratering, volcanism, tectonics, erosion.

47
Q

what is outgassing

A

the gasses from inside the earth are released during volcanism

48
Q

how does size of planet effect planet characteristics

A

cool off faster and harden earlier, promote volcanism and tectonics. also, more erosion because larger atmospheres from higher gravity

49
Q

how does distance from sun effect planet characteristics

A

too close means too hot, so no rain, snow or ice, so less erosion, and also difficulty retaining atmosphere. too far is too cold for rain, limiting erosion. liquid water = most erosion.

50
Q

how does speed of rotation effect planet characteristics

A

slower rotation means less weather, erosion, and weaker magnetic field. inverse for fast

51
Q

what is the effect of atmospheres on planets

A

create pressure to allow liquid water, scatter and absorb light (protective), create weather and climate. they interact with solar wind to create a magnetosphere, and can make planets warmer through the greenhouse effect

52
Q

how is planetary temperature achieved

A

difference between energy from sunlight it absorbs, and energy of outgoing thermal radiation. sunlight coming in, infrared going out.

53
Q

what is albedo

A

the albedo is the reflectivity of the planet, or what fraction of incoming light it reflects. planets with low albedo absorb more light, leading to higher temperatures

54
Q

how does the greenhouse effect work?

A

if most light sent to earth is visible, and it is absorbed on the surface, the earth gains energy. when energy is radiated off the earth as infrared, gasses in the atmosphere absorb the infrared light, not visible light, meaning it decreases the amount of energy lost by earth (or other planets)

55
Q

why is the sky blue

A

atmosphere scatters certain wavelengths of light, scattering the blue light, making it appear to come from many directions in the sky. however at sunset, the light travels through so much more atmosphere that the blue is mostly scattered (and lost) already, and the red photons are less scattered and therefore reach you

56
Q

what does the earths magnetic field do to solar wind

A

it protects us from solar wind by diverting it around the earth. these sometimes divert to the poles, exciting atmospheric molecules which are seen as aurora

57
Q

what is the difference between weather and climate

A

weather is the daily variations in wind, clouds, temperature and pressure, local and hard to predict, whereas climate is the long term average of weather, which is more stable and predictable, influenced by global conditions

58
Q

what are circulation cells?

A

wind rises in hot and drops in cool, meaning it creates cells of circulation from the equator, to cooler areas. this is over multiple cells when earth is rotating

59
Q

which 4 factors effect the atmosphere

A

solar brightening (sunlight increases over time), tilt of the axis (larger tilt creates more extreme seasons, and the tilt can wobble), changes in reflectivity (absorption of energy, ice reflects more, leading to positive feedback ice ages), greenhouse effect (amount of energy radiated by earth which is absorbed and retained by atmosphere)

60
Q

how can a planet gain an atmosphere

A

outgassing from volcanoes, evaporation of surface liquid or ice, impacts of particles and photons

61
Q

how can a planet lose an atmosphere

A

molecules have escape velocity, solar winds blow it away, condensation to surface, chemical reactions with surface, large impacts blasting gas to space

62
Q

how do gravity and thermal energy interact to shape the atmosphere

A

the thermal energy can give particles high enough energy to escape the atmosphere, but gravity intervenes, meaning that in hotter atmospheres, heavier particles are more likely to remain, and there will be a leakage of lighter particles (like hydrogen, compared to carbon dioxide staying)

63
Q

how are seasons on mars different to earth

A

similar tilt, but more of an elliptic orbit. this orbit means that seasons are more extreme on the southern hemisphere, which results in a CO2 ice cap on the northern hemisphere and a more H2O ice cap on the southern hemisphere

64
Q

how did climate change occur on mars

A

water once flowed on mars, however it at some point lost its atmosphere, resulting in the loss of the greenhouse effect, and therefore much colder temperatures

65
Q

describe the atmosphere of venus and its effect

A

venus has a very thick CO2 atmosphere, with a. strong greenhouse effect, with massive heats. also the slow rotation results in very little weathering

66
Q

how did venus’ atmosphere get so dense and hot

A

more intense sunlight caused water to evaporate, inflating the greenhouse effect, with oceans dissolving, and carbonate rocks decomposing to release more CO2

67
Q

Why did earth retain most of its outgassed water

A
68
Q

Why does earth have so little atmospheric carbon dioxide unlike venus

A
69
Q

Why does Earth’s atmosphere consist mostly of nitrogen and oxygen

A
70
Q

Why does Earth have an ultraviolet-absorbing stratosphere

A

Ultraviolet light breaks up atmospheric O2 molecules, forming O3 (Ozone). This ozone absorbs the ultraviolet light.

71
Q

Why does Earth have an ultraviolet-absorbing stratosphere

A
72
Q

How is earth’s climate relatively stable

A

When earth cools, CO2 builds up in the atmosphere, causing heating, and when it is heated, the weakened greenhouse effect cools the earth

73
Q

What causes earth’s long term climate change?

A

Changes in tilt, widespread ice leads to higher reflectivity of the earth (causing more ice), CO2 from outgassing when oceans are frozen builds up, rising the temp, and then melting permafrost releases more CO2.

74
Q

What causes earth’s long term climate change?

A

Changes in tilt, widespread ice leads to higher reflectivity of the earth (causing more ice), CO2 from outgassing when oceans are frozen builds up, rising the temp, and then melting permafrost releases more CO2.

75
Q

How did Jovian planets form

A

Frozen hydrogen compounds and other rocks formed planetesimals which built up, eventually gravitationally attracting H and He gas. Size decreases when they are further from sun, as the solar nebula was less dense.

76
Q

Why does Jupiter’s weather continue for so long?

A

There is no solid surface for friction to occur, and therefore, the storms can go for a long time. (Also Jupiter’s massive)

77
Q

Describe Europa

A

Largest of Jupiter’s moons, has a crust of ice, and a lot of liquid water underneath, with a strong magnetic field.

78
Q

Describe titan

A

largest Saturn moon, thick n2 atmosphere, lakes of ethane and methane.

79
Q

Describe Saturns rings

A

Very wide, but very thin. Particles orbit independently (lots of collisions). The moons in the rings guide the edges.

80
Q

Why do asteroids, comets and dwarf planets remain

A

The formation of planets was not 100% efficient, and therefore planitesmals and other smaller objects were left over.

81
Q

What are asteroids?

A

Rocky leftovers of planet formation, which orbit the sun. They are cratered, not round (misshaped because they are too small to have a big enough grav field to force round shape).

82
Q

What is the problem with orbital resonances of asteroids with planets.

A

If they have a resonance, orbiting at a particular fraction of a planet’s period, the asteroid will be pulled out of that orbit by the grav field of the planet as it gets the same point each time, and will be thrown off path.

83
Q

What are meteorites and meteors and what’s the difference?

A

A meteorite is a rock in space which falls through the Earth’s atmosphere, and a meteor is the bright trail left by particles hitting the atmosphere.

84
Q

What evidence do we have for the dinosaur impact extinction event

A

Scientists have found a worldwide iridium layer ~ 65 million years old. Iridium is very rare on earth surface rocks, but common in meteorites, meaning, likely there was a massive impact which killed the dinosaurs. Also, all dinosaur fossils are below the Iridium layer.

85
Q

What are comets

A

The icy counterparts to asteroids (orbit sun, but made of ice and dust). Comets reveal a tail when they get close to the sun and melt, with an ion tail, and a dust tail. Ion tail reveals direction of sun, as it is due to solar winds, and dust tail reveals direction of motion (bent by solar wind), as it is dust being left behind. The nucleus is the centre, and is just a dirty snowball.

86
Q

What is the Oort Cloud

A

The rot cloud is a cloud of comets which almost escaped the solar system, which get disturbed every so often, causing some to come back into the solar system, with massively elliptical orbits, unlike usual little ellipticity to normal comets.

87
Q

What is transmission of light

A

How light passes through objects, like transparent vs opaque

88
Q

Describe reflection and scattering of light

A

They change the direction of light, but not the energy

89
Q

What wavelengths are red, blue, and yellow light

A

Red = 700 nm, yellow = 550 nm, blue = 450nm.

90
Q

What is refraction

A

The bending of light as it passes from one substance into another

91
Q

What is the focal plane

A

The focal plane is the area where the light from different directions comes into focus.

92
Q

How does a camera focus light

A

The light goes through the lens, which is then let in by the opening of the shutter, and then captured by the CCD detector which is on the focal plane.

93
Q

What are the limits of the human eye

A
  • only collect a limited number of photons, meaning dim objects cannot be seen (eyes are small)
  • angular resolution is small (about 1 arc minute) (take two lights far away, we would see them as one)
  • wavelength range (only from 400-700nm)
94
Q

How can telescopes improve on the human eye?

A
  • larger apertures or longer exposures can facilitate viewing of further and dimmer objects
  • larger diameters let us have a better angular resolution (see objects closer together in greater detail)
  • differing receptors allow photos to be taken of different parts of the EM spectrum (reveal new info)
95
Q

What is the reason for angular resolution issues

A

As light is a wave, the superposition of the waves interfere with each other, meaning that at a certain distance, the waves blend together. The larger the aperture (diameter of telescope), the less the interference occurs, and more angular resolution is possible.

96
Q

What is the diffraction limit?

A

The limit of angular resolution. It decreases linearly with increased telescope aperture.

97
Q

How do refracting telescopes work and what are their drawbacks?

A

The lens refracts the light towards an eyepiece. They need to be very long with large lenses. This can be bad as they are very heavy, and hard to move, while limiting their apertures and therefore resolution.

98
Q

How do reflecting telescopes work, and what are their positives.

A

They focus the light with shaped mirrors, meaning that there is no heavy glass lens needed, allowing for much shorter and lighter telescopes, allowing much larger diameters, and therefore greater resolution.

99
Q

What are the optimal conditions for a telescope on earth?

A

Up high (less atmosphere), far from civilisation (limit light polution), dry (few cloudy nights), calm (not too windy)

100
Q

How does light pollution limit astronomy

A

The atmosphere scatters light produced by civilisation, which can impact astronomical images and observations.

101
Q

How does the earths atmosphere impact astronomical observations?

A

causes blurring of objects and twinkling of stars.

102
Q

Why do we put telescopes in space?

A

Limit light scattering from atmosphere, escape light pollution from humans, escape limits of day/night, escapes limits of weather (clouds).

103
Q

Which wavelengths can be observed on the earth’s surface?

A

Visible light, and Radiowaves.

Solar System Cosmos (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions