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WorksheetsEarth's Internal Layers
Total questions: 143
Worksheet time: 1hrs 12mins
Which statement best distinguishes continental crust from oceanic crust?
Continental crust is thinner and denser, mainly basalt.
Continental crust is thicker and less dense, mainly granite.
Oceanic crust is thicker and less dense, mainly granite.
Oceanic crust is thicker and denser, mainly basalt.
What is the lithosphere composed of, according to the description of Earth’s internal layers?
Only the crust
Only the upper mantle
The crust and the solid upper part of the mantle
The entire mantle
Which mantle sub-layer is described as semi-molten and "plastic-like," allowing lithospheric plates to float and move?
Lower mantle
Asthenosphere
Outer core
Inner core
Seismic S-waves cannot pass through which layer, and what key property of that layer explains this behavior?
Lower mantle; it convects slowly
Asthenosphere; it is semi-molten
Outer core; it is liquid metal
Inner core; it is solid metal
Which pairing correctly matches a core layer with its state of matter and a consequence of that state?
Outer core—solid; generates Earth's magnetic field
Inner core—liquid; remains liquid due to low pressure
Outer core—liquid; flow helps generate Earth's magnetic field
Inner core—liquid; S-waves cannot pass through it
The mantle is identified as the thickest layer of Earth. Approximately how thick is it?
30–70 km
5–10 km
~2900 km
~1200 km
Despite being hotter than the outer core, why is Earth's inner core solid?
It is composed mostly of granite.
Immense pressure keeps it solid.
It cools rapidly due to convection.
S-waves heat it and cause solidification.
According to plate tectonics, what do large lithospheric plates move over?
Inner core
Asthenosphere
Stratosphere
Exosphere
Which process primarily drives the motion of tectonic plates?
Atmospheric circulation
Ocean currents
Mantle convection
Solar radiation
At an oceanic–continental convergent boundary, which outcome is most likely?
Formation of mid-ocean ridges
Creation of deep-sea trench and volcanic mountain range on the continent
Development of transform faults
Formation of rift valleys
Which statement best distinguishes oceanic–oceanic convergence from continental–continental convergence?
Only continental–continental convergence forms volcanic island arcs.
Only oceanic–oceanic convergence involves subduction of the older, denser plate.
Both produce deep-sea trenches but not mountains.
Neither involves subduction.
Divergent plate boundaries are characterized by which primary process?
Buckling and folding of continental crust
Subduction of the denser plate beneath the less dense plate
Magma upwelling that creates new crust
Collision that forms volcanic island arcs
A geologist maps a chain of volcanic islands with an adjacent trench in the ocean. Which boundary type and mechanism best explain this observation?
Divergent boundary; magma rises to fill a gap
Transform boundary; lateral shear creates volcanism
Oceanic–oceanic convergent boundary; older, denser plate subducts
Continental–continental convergent boundary; neither plate subducts
Which reasoning best explains why the Himalayas contain very high mountains without an adjacent volcanic arc or deep-sea trench?
They formed at a divergent boundary where magma builds mountains.
They formed at a continental–continental convergent boundary where neither plate subducts, causing crustal buckling and thickening.
They formed above a mantle plume unrelated to plate boundaries.
They formed at an oceanic–continental boundary where subduction builds nonvolcanic mountains.
Which plate boundary is depicted where two plates move apart, forming a ridge and new oceanic crust through seafloor spreading?
Divergent plate boundary
Transform plate boundary
Convergent plate boundary
Intraplate hotspot
In the transform plate boundary diagram, what primary geologic effect is labeled along the plate margin?
Volcanic arc
Earthquakes
Mid-ocean ridge
Rift valley
At a convergent plate boundary shown in the diagram, which process is most directly responsible for volcanic activity near the overriding plate?
Subduction of one plate beneath another
Seafloor spreading
Horizontal shearing of plates
Continental rifting
According to the diagrams, which boundary neither creates nor destroys crust but commonly generates significant seismic activity?
Divergent boundary
Transform boundary
Convergent boundary
Hotspot boundary
Which boundary type is most directly associated with the formation of a mid-ocean ridge due to magma upwelling?
Convergent
Transform
Divergent
Collision-only continental
A geologist maps a linear valley on land aligned with plates moving apart, analogous to the oceanic ridge in the top diagram. Which feature is this most likely to represent?
Trench
Rift valley
Strike-slip fault scarp
Accretionary wedge
Which comparison best distinguishes the stress regimes at divergent and convergent boundaries as depicted?
Both are dominated by compressional stress
Divergent is tensional; convergent is compressional
Divergent is shear; convergent is tensional
Divergent and convergent are both shear
Which statement best describes a normal fault?
Hanging wall moves up due to compressional stress at convergent boundaries
Hanging wall moves down due to tensional stress at divergent boundaries
Plates slide horizontally past each other at convergent boundaries
Footwall moves down due to shear stress at transform boundaries
P-waves are characterized by which combination of properties?
Shear motion; travel only through solids; slower than S-waves
Compressional (push-pull) motion; travel through solids, liquids, and gases; fastest body waves
Surface-confined motion; cause the most damage; cannot pass through liquids
Rotational motion; travel through gases only; slowest overall
What is the key reason S-waves cannot travel through Earth’s outer core?
They are absorbed by gases
They require a liquid medium
They are shear waves that can only travel through solids
They are too slow to reach that depth
Which pair correctly matches fault type with dominant stress and boundary setting?
Reverse/thrust fault — shear stress — transform boundaries
Strike-slip fault — compressional stress — convergent boundaries
Normal fault — tensional stress — divergent boundaries
Normal fault — compressional stress — convergent boundaries
Magma viscosity primarily refers to:
Its temperature at eruption
Its resistance to flow
Its silica content exclusively
Its dissolved gas content only
High-viscosity magma tends to produce which eruption style and why?
Effusive eruptions because gases escape easily
Explosive eruptions because it traps gases
Effusive eruptions because it is thin and runny
No eruptions because it solidifies underground
Which volcano type is broad and gently sloping, formed primarily from low-viscosity lava flows with typically effusive eruptions?
Composite (stratovolcano)
Cinder cone
Shield volcano
Caldera complex
Composite (stratovolcano) eruptions are often highly explosive because they are formed from alternating layers of lava and ash sourced from which magma characteristic?
Low-viscosity magma
High-viscosity magma
Gas-poor magma
Ultrabasic magma
Which statement best defines the rock cycle?
The process by which sediments compact into rock only
The process by which rocks of one type change into rocks of another type
The sequence of volcanic eruptions that form mountains
The method used to classify minerals by hardness
Igneous rocks form through which primary process?
Weathering and erosion of existing rocks
Cooling and solidification of molten rock
Compaction and cementation of sediments
Heat and pressure without melting
Which pairing correctly matches an igneous subtype with its cooling environment and typical crystal size?
Intrusive — cools quickly at the surface; small crystals
Extrusive — cools slowly beneath the surface; large crystals
Intrusive — cools slowly beneath the surface; large crystals
Extrusive — cools slowly at the surface; large crystals
Which sequence correctly orders the major steps that turn loose sediments into sedimentary rock?
Deposition → Weathering & Erosion → Melting
Compaction & Cementation → Deposition → Weathering & Erosion
Weathering & Erosion → Deposition → Compaction & Cementation
Heat & Pressure → Melting → Solidification
Which sedimentary rock category forms from minerals precipitating directly from water?
Clastic
Organic
Chemical
Foliated
Metamorphic rocks form primarily through which condition?
Cooling of magma at depth
Heat and pressure that change rock without melting
Compaction of fragments during lithification
Rapid quenching of lava at the surface
Which description distinguishes foliated from non-foliated metamorphic rocks?
Foliated rocks show aligned grains in parallel bands; non-foliated show no bands
Foliated rocks are always igneous; non-foliated are always sedimentary
Foliated rocks are formed at the surface; non-foliated form deep underground
Foliated rocks contain fossils; non-foliated do not
A sandstone is buried and subjected to intense heat and pressure without melting. Which metamorphic rock is it most likely to become?
Marble
Basalt
Gneiss
Quartzite
According to the diagram, which process directly transforms magma into igneous rock?
Melting
Cooling
Compaction and cementation
Weathering and lithification
Heat and pressure
Which statement best defines weathering as presented in the material?
The movement of rock from one place to another
The in-place breakdown of rock
The heating and melting of rock
The transformation of sediment into sedimentary rock
Mechanical (physical) weathering is described as breaking rock into smaller pieces. Which example listed is a direct cause of this process?
Chemical dissolution by acid rain
Frost wedging
Regional metamorphism
Compaction and cementation
Based on the cycle, which pair of processes can convert sediment into sedimentary rock and then further into metamorphic rock?
Melting; Cooling
Compaction and cementation; Heat and pressure
Weathering and lithification; Melting
Cooling; Weathering and lithification
A granite boulder cracks over winter as water in its joints freezes and expands. Which mechanism from the material best explains this observation?
Abrasion
Chemical precipitation
Root wedging
Frost wedging
Windblown sand scours exposed bedrock in a desert, gradually smoothing the surface. Which mechanical weathering example fits this scenario?
Abrasion
Compaction
Lithification
Cooling
Which process is an example of chemical weathering that involves oxygen reacting with minerals, often causing rusting?
Erosion
Oxidation
Deposition
Compaction
Relative dating primarily determines which of the following?
The exact numerical age in years
The order of events compared to one another
The chemical composition of a rock
The rate of plate motion
Which method is commonly used for absolute dating by determining the actual age of rocks or fossils?
Cross-cutting relationships
Radiometric dating
Biostratigraphy only
Superposition alone
During which eon did simple life such as bacteria appear and which constitutes about 88% of Earth’s history?
Phanerozoic Eon
Precambrian Time
Cenozoic Era
Mesozoic Era
Match each Phanerozoic era with its nickname.
Paleozoic — Age of Mammals; Mesozoic — Age of Reptiles; Cenozoic — Age of Invertebrates & Fish
Paleozoic — Age of Invertebrates & Fish; Mesozoic — Age of Reptiles; Cenozoic — Age of Mammals
Paleozoic — Age of Reptiles; Mesozoic — Age of Mammals; Cenozoic — Age of Invertebrates & Fish
Paleozoic — Age of Invertebrates & Fish; Mesozoic — Age of Mammals; Cenozoic — Age of Reptiles
A river loses energy and drops sediments, forming landforms. Which process and resulting features are best described here?
Erosion forming canyons
Deposition forming deltas, alluvial fans, and beaches
Oxidation forming rust layers
Hydrolysis forming clay minerals
Which pair correctly identifies a hydrologic cycle process and its description?
Evaporation — water vapor condenses into liquid
Transpiration — water vapor is released from plants
Evaporation — liquid water freezes into ice
Transpiration — groundwater seeps into rivers
A basalt sample is tested for radioactive isotope decay to determine its age in years. Which dating approach and justification best apply?
Relative dating, because it compares layers above and below
Absolute dating, because it calculates an actual numerical age via radiometric methods
Relative dating, because fossils indicate environment
Correlation dating, because it matches rock types across regions
In the hydrologic cycle diagram, which process directly forms clouds by water vapor turning back into liquid?
Evaporation
Condensation
Infiltration
Runoff
Which sequence best represents precipitation in the water cycle as described?
Water vapor rises from oceans and lakes
Water falls from clouds as rain, snow, sleet, or hail
Water gathers in rivers, lakes, and oceans
Water soaks into the ground becoming groundwater
According to the diagram and labels, which pathway represents water moving across land before entering bodies of water?
Surface flow (runoff)
Infiltration
Underground flow
Condensation
Which statement best differentiates infiltration from runoff in the hydrologic cycle?
Infiltration is water evaporating into the atmosphere; runoff is water condensing into clouds.
Infiltration is water soaking into the ground; runoff is water flowing over the land surface.
Infiltration is water collecting in oceans; runoff is groundwater movement.
Infiltration is ice melting; runoff is snow formation.
Which of the following is identified as a constructive force in landform development?
Weathering
Erosion
Deposition
Ice carving
A delta forming at a river mouth is primarily the result of which process?
Erosion removing sediment from the coast
Deposition building up sediment where water slows
Weathering breaking rock into smaller pieces
Runoff transporting water overland only
Given a coastline shaped by wind, water, and ice carving valleys and cliffs, which category of forces is most responsible?
Constructive forces such as volcanism
Destructive forces such as weathering and erosion
Plate tectonics only
Condensation and precipitation
What primary cause drives atmospheric circulation on Earth?
Rotation of the Moon around Earth
Unequal heating of the Earth by the Sun
Tidal forces in the oceans
Volcanic outgassing
In the three-cell model, where does air rise and later sink to create deserts around 30° latitude?
Ferrel Cell
Polar Cell
Hadley Cell
ITCZ Cell
Which cell operates primarily in the mid-latitudes (30°–60°)?
Hadley Cell
Ferrel Cell
Polar Cell
Equatorial Cell
The Coriolis Effect causes winds to curve in which directions in each hemisphere?
Right in the Northern Hemisphere and left in the Southern Hemisphere
Left in both hemispheres
Right in both hemispheres
Left in the Northern Hemisphere and right in the Southern Hemisphere
Which global wind patterns are cited as outcomes of the Coriolis Effect acting on atmospheric circulation?
Monsoons and sea breezes
Trade Winds and Westerlies
Land breezes and katabatic winds
Jet streams and chinooks
Which location correctly matches the cell predominantly found at the poles (60°–90°)?
Ferrel Cell at the poles
Polar Cell at the poles
Hadley Cell at the poles
Hadley–Ferrel Cell at the poles
Reasoning: If the Sun heated the poles more than the equator, which of the following changes to atmospheric circulation would most likely occur?
Pressure differences would weaken, reducing wind formation
Hadley circulation would reverse, with sinking at the equator and rising near 30°
The three-cell model would collapse into a single global cell with rising air at the poles
Global wind patterns like the Trade Winds would likely shift or reverse due to altered pressure gradients
Refer to the labeled global circulation diagram showing Hadley, Ferrel, and Polar cells. Which sequence from the equator to the pole correctly lists the major circulation cells in one hemisphere?
Hadley → Polar → Ferrel
Ferrel → Hadley → Polar
Hadley → Ferrel → Polar
Polar → Ferrel → Hadley
According to the diagram, at approximately which latitude belt do Ferrel cells dominate?
Near the equator (0°)
Between about 30° and 60°
Above 60° toward the poles
Exactly at 30° only
Which statement best distinguishes weather from climate as defined in the material?
Weather describes long-term averages; climate describes short-term conditions at a specific location.
Weather is the short-term conditions at a specific location; climate is the long-term average over a large region.
Weather and climate both refer to day-to-day conditions but at different altitudes.
Climate only concerns rainfall while weather only concerns temperature.
Based on the definitions provided, which example correctly illustrates climate rather than weather?
It is 30°C and sunny in Manila today.
A thunderstorm is expected this afternoon in Jakarta.
The Philippines has a tropical marine climate.
Fog is reducing visibility this morning in London.
The material states that the natural greenhouse effect is a necessary process. What is its primary role as described?
To remove greenhouse gases from the atmosphere
To trap some heat in the atmosphere
To cool Earth by reflecting sunlight back to space
To create the Hadley cell circulation
Which of the following is listed as a greenhouse gas contributing to the natural greenhouse effect in the material?
Oxygen (O2)
Nitrogen (N2)
Water vapor (H2O)
Argon (Ar)
Considering the circulation belts shown, which cell is directly poleward of the Ferrel cell in each hemisphere?
Hadley cell
Polar cell
Another Ferrel cell
Intertropical Convergence Zone
Which term describes the imaginary giant sphere surrounding Earth used to map positions of stars and constellations?
Celestial Sphere
Thermosphere
Magnetosphere
Corona
Earth's rotation is responsible for which daily phenomenon?
Phases of the Moon
Day and night
Seasons
Solar eclipses
Approximately how long does one complete rotation of Earth take?
12 hours
24 hours
7 days
365 days
Earth's revolution around the Sun primarily causes which pattern, influenced by Earth's 23.5° axial tilt?
Tides
Seasons
Daylight saving time
Plate tectonics
Which sequence lists common lunar phases mentioned in the material?
Gibbous, Crescent, Supermoon
New Moon, Full Moon, Quarter
First Light, Zenith, Nadir
Wax-off, Wan-on, Quarter
During a solar eclipse, the Moon's position relative to Earth and the Sun is best described as:
Behind Earth
Between the Sun and Earth
Behind the Sun
Farther from both Earth and the Sun
What occurs during a lunar eclipse according to the material?
The Sun passes between Earth and the Moon
Earth passes between the Sun and Moon, casting a shadow on the Moon
The Moon casts a shadow on the Sun
The Moon disappears due to new moon phase
Which statement best contrasts the geocentric and heliocentric models?
Geocentric places the Sun at the center; heliocentric places Earth at the center
Both place Earth at the center
Geocentric places Earth at the center; heliocentric places the Sun at the center
Both place the Sun at the center
Who is associated with proposing the correct heliocentric model in the material?
Ptolemy
Galileo
Copernicus
Kepler
Kepler's first law states that planets orbit in which type of paths?
Circles
Parabolas
Hyperbolas
Ellipses
According to Kepler's second law, when does a planet move faster in its orbit?
When closer to the Sun
At aphelion only
When farther from the Sun
Always at a constant speed
Kepler's third law identifies a mathematical link between which two quantities?
Planet mass and radius
Planet distance from the Sun and its orbital time
Star temperature and brightness
Planet tilt and season length
Newton's Law of Universal Gravitation explains which underlying cause of Kepler's laws?
Electromagnetism between planets
All objects with mass attract each other
Solar wind pressure
Inertia alone without forces
Where in the Sun does nuclear fusion occur according to the material?
Photosphere
Corona
Core
Chromosphere
What is the photosphere of the Sun?
The Sun's magnetic field
The visible surface of the Sun
The Sun's dense core
The outer solar wind region
Which solar feature is described as the hot, thin outer atmosphere visible during a total solar eclipse?
Core
Photosphere
Corona
Radiative zone
Which set correctly lists the terrestrial (inner) planets highlighted in the material?
Mercury, Venus, Earth, Mars
Jupiter, Saturn, Uranus, Neptune
Earth, Jupiter, Saturn, Mars
Mercury, Earth, Jupiter, Neptune
How are terrestrial planets characterized in the material?
Large, low-density, gas-rich
Small, rocky, dense
Ice-rich, ring-dominated
Water worlds with thick atmospheres
Which planets are identified as gas giants and primarily composed of Hydrogen and Helium?
Mercury and Venus
Earth and Mars
Jupiter and Saturn
Uranus and Neptune
Jovian (outer) planets are best described as:
Small and rocky
Large and low-density
Small with no atmospheres
Rocky with solid surfaces
Which region contains most asteroids in our solar system?
Between Earth and Mars
Asteroid Belt between Mars and Jupiter
Kuiper Belt beyond Neptune
Oort Cloud far beyond the Kuiper Belt
Comets are best described as which of the following?
Metal-rich planets that formed near the Sun
Dirty snowballs of ice, rock, and dust from the Kuiper Belt and Oort Cloud
Gas giants dominated by hydrogen and helium
Small moons captured by Jupiter
What distinguishes a dwarf planet from a major planet according to the provided definition?
It does not orbit the Sun
It lacks a nearly round shape
It has not cleared its orbital neighborhood
It is made only of rock and metal
According to the EM spectrum diagram, which type of electromagnetic radiation has the longest wavelength and lowest energy?
Ultraviolet
Infrared
Microwaves
Radio waves
Which statement about the electromagnetic (EM) spectrum is supported by the material?
It includes only the visible colors our eyes can see
Most light in the EM spectrum is invisible to our eyes
Energy increases with increasing wavelength
X-rays have lower energy than infrared
Spectroscopy, as defined here, primarily helps astronomers determine which set of properties of a star?
Age, distance, and diameter
Composition, temperature, and speed
Mass, luminosity, and radius
Magnetic field strength, age, and parallax
A newly observed object is small, rocky, nearly round, orbits the Sun, and shares its orbit with many other bodies. Based on the definitions provided, how should it be classified?
Asteroid
Comet
Dwarf planet
Ice giant
Which process powers a star by fusing light elements into heavier ones and releasing energy according to E=mc2 ?
Nuclear fission
Nuclear fusion
Radioactive decay
Gravitational lensing
Hydrostatic equilibrium in a star occurs when which two effects are balanced?
Magnetic fields and radiation pressure
Outward pressure from fusion and inward pull of gravity
Centrifugal force and radiation pressure
Convection and conduction
On a Hertzsprung–Russell (H–R) diagram, what two properties are plotted on the axes?
Mass vs. age
Radius vs. metallicity
Luminosity (brightness) vs. temperature (color)
Distance vs. apparent magnitude
Where do stars, including the Sun, spend most of their lifetimes on the H–R diagram?
White dwarf region
Supergiant branch
Main Sequence band
Giant clump
According to the diagram, which temperature range corresponds to blue, very hot stars with high luminosity such as Rigel?
Around 3,000 K
Around 6,000–7,000 K
Around 10,000–30,000 K
Below 1,000 K
As stars cool from about 7,000 K toward 3,000 K on the H–R diagram, their color trend is best described as
Blue to red
Red to blue
White to blue
Green to yellow
Which sequence correctly describes the life cycle of a low-mass star like the Sun?
Nebula → Red Supergiant → Supernova → Neutron Star
Nebula → Main Sequence → Red Giant → Planetary Nebula → White Dwarf
Nebula → Main Sequence → Supernova → Black Hole
Protostar → Blue Supergiant → Supernova → White Dwarf
For a high-mass star, which event differentiates its late evolution from that of a low-mass star?
Formation of a planetary nebula
Hydrogen fusion on the Main Sequence
A supernova following the Red Supergiant phase
Cooling into a white dwarf without mass loss
According to the evolution diagram, what stage directly follows a red supergiant in a high-mass star’s life cycle?
Planetary nebula
Supernova
White dwarf
Main-sequence star
In the Milky Way’s structure, which component is described as the flat, rotating region containing spiral arms, young stars, gas, and dust?
Halo
Central bulge
Disk
Sagittarius A*
What is Sagittarius A* (Sgr A*) in the context of the Milky Way?
A dwarf galaxy orbiting the Milky Way
A supermassive black hole at the exact center
A prominent spiral arm
A star cluster in the halo
Which outcome can result if a high-mass star is massive enough after a supernova?
White dwarf
Planetary nebula
Black hole
Brown dwarf
Which galaxy type is characterized as smooth and oval-shaped with mostly old, red stars according to the Hubble tuning fork categories?
Spiral
Elliptical
Irregular
Barred spiral
Reasoning with the diagram, which pair correctly matches a Milky Way component with its dominant stellar population?
Disk — mostly old, red stars
Central bulge — young stars and star-forming gas
Halo — old stars
Halo — supermassive black hole
Using the Hubble tuning fork categories, which description best fits an irregular galaxy?
Disk-shaped with spiral arms
No clear shape, often from galactic collisions
Oval-shaped with mostly old, red stars
Ring-shaped with central void
Which statement best describes the Big Bang Theory as presented?
The universe has always existed in its current state
The universe began from an infinitely hot, dense state and has been expanding and cooling
The universe started cold and has been heating up
Galaxies formed before the universe began
During which early epoch did the universe undergo exponential expansion shortly after the Big Bang?
Recombination
Big Bang Nucleosynthesis
Inflation
Galaxy formation
According to the material, about how long after the Big Bang did Big Bang Nucleosynthesis occur?
First fraction of a second
First 3 minutes
About 380,000 years
About 13.8 billion years
What approximate elemental composition resulted from Big Bang Nucleosynthesis?
50% Hydrogen and 50% Helium
90% Hydrogen and 10% Helium
75% Hydrogen and 25% Helium
60% Hydrogen and 40% Helium
What major physical change occurred at recombination, approximately 380,000 years after the Big Bang?
Protons and neutrons first formed atomic nuclei
Electrons combined with nuclei to form the first atoms, making the universe transparent
Dark energy began accelerating expansion
Stars ignited across the universe
Which sequence correctly orders the listed key Big Bang events from earliest to latest?
Recombination → Inflation → Big Bang Nucleosynthesis
Inflation → Big Bang Nucleosynthesis → Recombination
Big Bang Nucleosynthesis → Inflation → Recombination
Inflation → Recombination → Big Bang Nucleosynthesis
What ongoing trend of the universe is emphasized by the Big Bang framework in this lesson?
Static size and constant temperature
Contracting and heating
Expanding and cooling
Oscillating between expansion and contraction each century
Which observation directly supports universal expansion according to Hubble’s Law?
Blue-shift of nearby stars indicates collapse
Redshift of distant galaxies increases with distance
Constant brightness of standard candles across all distances
Uniform distribution of heavy elements in galaxies
What is the Cosmic Microwave Background (CMB) as described in the material?
A recent burst of gamma rays from black holes
The faint microwave afterglow from the Recombination event filling all space
Thermal radiation emitted only by present-day stars
Radio noise produced by Earth’s atmosphere
The observed primordial abundance of light elements is closest to which ratio?
50% hydrogen / 50% helium
75% hydrogen / 25% helium
25% hydrogen / 75% helium
90% hydrogen / 10% helium
In the diagram, the large-scale structure described as the 'Cosmic Web' consists primarily of which features?
Randomly distributed galaxies with no pattern
Filaments and clusters separated by voids
Only isolated spiral galaxies
Uniform gas clouds without galaxies
According to the section, which statement best explains redshift in the context of the Big Bang evidence?
Light gains energy as it travels, shifting to bluer wavelengths
Space between galaxies shrinks, stretching light to redder wavelengths
Light from distant galaxies is stretched to longer wavelengths as the universe expands
Stars within the Milky Way emit only red light
Which scenario describes the most likely long-term fate of the universe noted in the material?
Big Crunch: universal collapse into a single point
Big Rip: all structures torn apart by accelerating expansion
Steady State: no overall change through time
Big Freeze/Heat Death: expansion continues until stars burn out and energy is too spread out
Which sequence on the timeline corresponds to early-universe milestones highlighted in the figure?
First light from atoms after recombination, then dark ages, followed by galaxy formation
Galaxy formation, then recombination, then inflation
Solar system formation, then dark ages, then inflation
Recombination after the first stars formed
Which statement best reflects General Relativity as presented?
Gravity is a force pulling objects together in empty space.
Gravity results from the curvature or warping of spacetime by mass and energy.
Gravity is caused by electromagnetic interactions at large scales.
Gravity only affects objects with atmospheres.
What astronomical phenomenon is described as the bending of light from a distant object due to a massive foreground object, creating multiple or distorted images?
Redshift
Nuclear fusion
Gravitational lensing
Parallax
In the context of black holes, what is the Event Horizon?
The disk of material orbiting the black hole
The region where nuclear fusion resumes
The point of no return beyond which not even light can escape
The infinitely dense center where physics breaks down
Which pairing correctly matches the cosmic component with its role, according to the notes?
Dark Matter — causes the expansion of the universe to accelerate
Dark Energy — provides gravitational scaffolding for galaxies
Dark Matter — invisible matter inferred from its gravitational pull
Dark Energy — ordinary matter that we can directly observe
Which statement about exoplanets and habitability is consistent with the material?
Exoplanets only orbit stars identical to the Sun.
The Habitable Zone is where temperatures allow liquid water on a planet’s surface.
Exoplanets are limited to our Solar System’s outer regions.
Habitability requires an atmosphere identical to Earth's.
In Disaster Risk Reduction (DRR), which pair best represents the two main emphases stated?
Prediction and response
Mitigation (prevention) and preparedness
Reconstruction and insurance
Evacuation and rescue
Which of the following is NOT listed as a hazard associated with typhoons (Bagyo) in the Philippines?
Strong winds
Storm surge
Intense rain leading to flooding and landslides
Liquefaction of ground
Which agency issues Public Storm Warning Signals (PSWS) in the Philippines, and which preparedness action is mentioned?
PHIVOLCS; tsunami mapping
PAGASA; preparing Go Bags
NDRRMC; post-disaster housing
DENR; volcanic gas monitoring
Which Philippine agency is responsible for monitoring and reporting on earthquakes and volcanoes?
PAGASA
PHIVOLCS
DENR
NDRRMC
During an earthquake, which immediate safety action is recommended as a preparedness drill?
Run outside quickly
Duck, Cover, and Hold
Stand in a doorway and watch
Call a friend
Which of the following is NOT listed as a volcanic hazard?
Lava flows
Ash fall
Pyroclastic flows
Sea-level rise
PHIVOLCS uses a 5-level alert system for volcanoes. What does Level 5 indicate?
Normal
Increased monitoring
Eruption in progress
Minor unrest
Which mitigation measure is specifically mentioned to reduce risk around volcanoes?
Building taller houses
Establishing Permanent Danger Zones (PDZs)
Planting more trees
Opening tourist trails
Which earthquake hazard involves buildings losing foundation strength due to water-saturated soils behaving like a liquid?
Ground shaking
Liquefaction
Aftershocks
Lahar
When PHIVOLCS issues evacuation orders due to ash fall and potential pyroclastic flows, which preparedness action should communities prioritize?
Heeding the orders and preparing for ash fall
Holding a community festival
Waiting for lava flows to cool
Traveling into the PDZ to gather data
