EAPS 105 EXAM 2 QUESTIONS WITH VERIFIED
ANSWERS
The consequences of a planet or moon being hot inside
differentiation, volcanism, plate tectonics, magnetic fields
How hot the Earth is on the inside compared to the surface of the Sun
the inner core is almost as hot as the surface of the Sun, but is solid because the higher pressure
raises the melting temperature
The relationship between heat and motion in atoms
when an object is stopped, the kinetic energy is converted into atomic scale motion (vibration of
atoms), which is the very definition of heat
How core formation leads to an increase in internal temperature
the motion of the falling iron is converted into deformation at the surface of the growing core,
producing heat
Why Io is hot inside
Io's elliptical orbit around Jupiter causes the gravitational force between the two to vary,
changing how much Io's shape distorts as it orbits. This deformation generates enough heat to
melt Io's interior making it the most volcanically active body in the Solar System
How radioactive decay produces heat
radioactive decay is the process through which the nucleus of an unstable atom transforms into a
stable one by throwing off neutrons or protons, causing collisions that produce heat
Why smaller planets cool faster than larger ones
less primordial heat (less impacts smaller core), less radioactive elements to keep them hot,
smaller bodies have larger surface areas compared to volume: can more efficiently get rid of heat
How heat is transferred with conduction, convection, and radiation
convection: heat transfer through fluid motions of liquids and gases, as well as solids that flow
like a fluid.
conduction: heat transfer through a solid that does not readily flow,
radiation: heat transfer through electromagnetic waves through a transparent medium
How heat is transferred within each of Earth's interior layers
inner core: conduction, outer core: convection, mantle: solid-state convection, lithosphere:
conduction
What the lithosphere is on Earth
, the cold, strong outer region of a planet or moon that includes the crust and outermost mantle
What causes tectonic plates to move
the process by which the lithosphere is broken into plates and moves in response to mantle
convection
What mid-ocean ridges and subduction zones are
mid-ocean ridge:Underwater ridges where subduction (of crust/ lithosphere) and uplift (of the
mantle) occur
subduction zone: Area where one tectonic plate slips under another and into the mantle
Which of the other terrestrial planets currently exhibit plate tectonics
None, all the other planets are single plate planets
Why are there thrust faults on the surface of Mercury and the Moon
the interiors are continually cooling causing the surface to contract
What happened on Venus about 500 million years ago
the entire planet was resurfaced by volcanism
The requirements for a planet to generate a magnetic field
an electrical conducting fluid layer (like, but not necessarily, a liquid iron outer core), the layer
must be convecting so that the electricity is generated by the motion of the fluid, the planet must
have a fast spin so that the convection organizes itself into coils like that of any induced
magnetic field
What a magnetosphere is
the region where a planet's magnetic field is the predominant magnetic field
Why Venus does not have a magnetic field
it spins too slowly (243 Earth days per rotation) to organize convection in its liquid iron core into
coils
Why Jupiter and Neptune have magnetic fields
Jupiter's moon, Io, provides a portion charged particles to Jupiter's magnetosphere, Jupiter has a
liquid metallic hydrogen core, Neptune has chemistry of liquid ammonia/methane ice that cause
the field
The types of volcanism observed on each terrestrial planet
mid-ocean ridges and subduction zones in planets with tectonic plates, hot spots in planets
without tectonic plates
Know that mantles are mostly not melted rock (magma)
ANSWERS
The consequences of a planet or moon being hot inside
differentiation, volcanism, plate tectonics, magnetic fields
How hot the Earth is on the inside compared to the surface of the Sun
the inner core is almost as hot as the surface of the Sun, but is solid because the higher pressure
raises the melting temperature
The relationship between heat and motion in atoms
when an object is stopped, the kinetic energy is converted into atomic scale motion (vibration of
atoms), which is the very definition of heat
How core formation leads to an increase in internal temperature
the motion of the falling iron is converted into deformation at the surface of the growing core,
producing heat
Why Io is hot inside
Io's elliptical orbit around Jupiter causes the gravitational force between the two to vary,
changing how much Io's shape distorts as it orbits. This deformation generates enough heat to
melt Io's interior making it the most volcanically active body in the Solar System
How radioactive decay produces heat
radioactive decay is the process through which the nucleus of an unstable atom transforms into a
stable one by throwing off neutrons or protons, causing collisions that produce heat
Why smaller planets cool faster than larger ones
less primordial heat (less impacts smaller core), less radioactive elements to keep them hot,
smaller bodies have larger surface areas compared to volume: can more efficiently get rid of heat
How heat is transferred with conduction, convection, and radiation
convection: heat transfer through fluid motions of liquids and gases, as well as solids that flow
like a fluid.
conduction: heat transfer through a solid that does not readily flow,
radiation: heat transfer through electromagnetic waves through a transparent medium
How heat is transferred within each of Earth's interior layers
inner core: conduction, outer core: convection, mantle: solid-state convection, lithosphere:
conduction
What the lithosphere is on Earth
, the cold, strong outer region of a planet or moon that includes the crust and outermost mantle
What causes tectonic plates to move
the process by which the lithosphere is broken into plates and moves in response to mantle
convection
What mid-ocean ridges and subduction zones are
mid-ocean ridge:Underwater ridges where subduction (of crust/ lithosphere) and uplift (of the
mantle) occur
subduction zone: Area where one tectonic plate slips under another and into the mantle
Which of the other terrestrial planets currently exhibit plate tectonics
None, all the other planets are single plate planets
Why are there thrust faults on the surface of Mercury and the Moon
the interiors are continually cooling causing the surface to contract
What happened on Venus about 500 million years ago
the entire planet was resurfaced by volcanism
The requirements for a planet to generate a magnetic field
an electrical conducting fluid layer (like, but not necessarily, a liquid iron outer core), the layer
must be convecting so that the electricity is generated by the motion of the fluid, the planet must
have a fast spin so that the convection organizes itself into coils like that of any induced
magnetic field
What a magnetosphere is
the region where a planet's magnetic field is the predominant magnetic field
Why Venus does not have a magnetic field
it spins too slowly (243 Earth days per rotation) to organize convection in its liquid iron core into
coils
Why Jupiter and Neptune have magnetic fields
Jupiter's moon, Io, provides a portion charged particles to Jupiter's magnetosphere, Jupiter has a
liquid metallic hydrogen core, Neptune has chemistry of liquid ammonia/methane ice that cause
the field
The types of volcanism observed on each terrestrial planet
mid-ocean ridges and subduction zones in planets with tectonic plates, hot spots in planets
without tectonic plates
Know that mantles are mostly not melted rock (magma)
