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Flashcards in Week 4 Deck (50)
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1
Q

Are the properties of earths atmosphere the same wherever you are?

A

No, the Properties of atmosphere depend on height you are at becasue different energies will be absorbed at different heights

2
Q

Electromagnetic field

A

Molten Metallic core is electrically conducting, and the earth spinning on its axis activated convective currents in the core cause a magnetic field.

3
Q

Ozone layer

A

created by UV breaking apart oxygen molecules

4
Q

Atmosphere effects

A

Create pressure (determines presence of liquid water on surface), absorb/scatter light, create weather, protects from solar wind, warm through greenhouse effect.

5
Q

Lithosphere

A

Ridgid part of interior, that is part of crust and mantle

6
Q

Dissociation

A

Distruction of a molecule (UV/xray)

7
Q

Impact cratering

A

Something smashes into the surface (asteroid/comet)

8
Q

Planetary temperature

A

depends on energy in/energy out

9
Q

Conduction

A

Energy can transfer through material

10
Q

Stratosphere

A

UV absrobed due to ozone layer

11
Q

Moon interior

A

Small core, large Lithosphere

12
Q

Why is the earths core hot?

A

After planet accretion and differentiation, it Lost potential energy = gain kinetic energy (heat)

13
Q

Mercury interior

A

Almost all metalic core

14
Q

Why are sunsets red

A

Red light scatters less

15
Q

Weather

A

Day by day variations

16
Q

Affect of distance from sun

A

Too close to sun:

  • less erosion (as no wind, ice snow rain)
  • to hot for atmosphere
17
Q

Why is the core denser than the crust?

A

differentiation, i.e. gravity pulls high density stuff to core, light material rises to surface

18
Q

Why are mercury and the moon geologically dead?

A

They had a large surface area to volume ratio, so they cooled more quickly

19
Q

Lunar maria

A

Highlands =higher, cratered regions

Maria = lower, smoother less cratered regions (formed latter on)

20
Q

Surface age based on crattering

A

Highly cratered surface = surface formed early

Minimal craters = surface formed latter on

21
Q

Mars interior

A

large Lithosphere

22
Q

Convection

A

Bulk motion

23
Q

Why is the sky blue?

A

Atmosphere scatters blue light from sun

24
Q

What is an atmosphere

A

a layer of gas that surrounds a plannet

25
Q

Climate

A

Long term average

26
Q

magnetosphere

A

Interaction between atmosphere and solar wind, which Prevents its charged particles crashing into earth

27
Q

Earth atmosphere

A

10km thick, consisting of mainly nitrogen and oxygen

28
Q

erosion

A

Surface changes by wind, water, ice

29
Q

Interior of terrestrial planet

A

Metal Core, mantle, crust (in order of decreasing density)

30
Q

Mercury cliff casues

A

Shrinking of core and mantle caused buckling and resulted in cliff formation

31
Q

Why did earth retain most of its outgassed water?

A

Cool enough (distance from sun) for liquid oceans to form

32
Q

P waves

A

Waves that push back and forth, Goes through core

33
Q

Why does earth have little carbon dixoide in atmosphere?

A

Has a lot of liquid water and carbon dioxide is very soluble in water

34
Q

Absorbtion

A

Photons energy is absorbed (IR)

35
Q

Scattering

A

Change in photon direction (optical)

36
Q

Factors affecting atmosphere

A

Solar brightening, axis tilt, reflectivity, geen house gases

37
Q

Albedo

A

Amount a planet reflects incoming sunlight

38
Q

Ionization

A

removal of electron (UV/xray)

39
Q

Radiation

A

Photons/light sent into space

40
Q

Volcanism

A

eruption of molten rock onto surface

41
Q

S waves

A

Waves move transverse to direction of motion (side to side), they don’t go through the core

42
Q

Techtonics

A

disruption of a planets surface by internal stressed, as a result of convection currents (mountains or valleys)

43
Q

The ‘lithosphere’ of a planet is

A

the rigid rocky material of the crust and upper part of the mantle

44
Q

What could a decreasing albedo cause?

A

Gradual warming of climate

45
Q

How does the cooling of planets vary with size?

A
  • Larger size makes it harder for heat from the inside to escape,
  • Larger size means bigger ratio of volume to surface ratio
  • Larger size takes longer to cool
46
Q

Earth’s atmosphere contains just a small amount of carbon dioxide at the present time, because

A

Carbon dioxide dissolves in water, and now most of it is contained in oceans and carbonate rocks

47
Q

What is necessary for differentiation to occur in a planet?

A
  • It must be a mixture of materials with different densities

- The materials inside the planet must be able to flow

48
Q

The cores of terrestrial planets are mostly metal because

A

Metals are denser and so sank to the centres of planets when they were still molten

49
Q

Heat escapes from a planet’s surface by thermal radiation. This means that planets radiate almost entirely in the wavelength range of

A

Infrared

50
Q

What are the conditions necessary for a terrestrial planet to have a strong magnetic field?

A

Both a molten metallic core and fairly fast rotation