WorksheetsScience 8 Quarter 3
Total questions: 47
Worksheet time: 24mins
Approximately what percentage of the Earth’s total surface area is covered by water?
29%
71%
70%
97%
Which of the following best describes the distribution of Earth’s surface area based on the known proportions of land and water?
The water to land surface ratio is approximately 7:3.
The surface is divided into approximately 3/4 land and 1/4 water.
The amount of land is nearly equal to the amount of water across the globe.
Water covers about 97% of the total surface, while land covers only 3%.
A student uses 100 tiles to build a flat model of Earth. How many tiles should be colored green to represent the land?
29 tiles
30 tiles
71 tiles
70 tiles
Based on rock composition, which pair primarily makes up the continental and oceanic crusts, respectively?
Continental: Granitic; Oceanic: Peridotitic
Continental: Granitic; Oceanic: Basaltic
Continental: Peridotitic; Oceanic: Basaltic
Continental: Basaltic; Oceanic: Granitic
Based on the chemical composition of crustal material, which two elements together make up approximately three-quarters of its total mass?
Silicon and Aluminum
Oxygen and Silicon
Aluminum and Sodium
Potassium and Oxygen
Why does the oceanic crust usually sink beneath the continental crust during subduction into the layer below?
Continental crust rocks are older and composed of heavier materials.
The oceanic crust is much thicker and heavier.
Oceanic crust rocks are denser and more compact.
The weight of the seawater pushes the oceanic crust downward.
A researcher finds two samples from the Earth's surface. Sample X is light-colored with large, visible crystals. Sample Y is dark-colored, very dense, and has a fine-grained texture. Where did these samples most likely originate?
Both samples originated from the same layer under the mountain ranges.
Sample X is from the mantle; Sample Y is from the continental crust.
Sample X is from the ocean floor; Sample Y is from the continents.
Sample X is from the continental crust; Sample Y is from the oceanic crust.
Which of the following is the primary factor used by volcanologists to classify a volcano as "active" rather than "dormant"?
A record of eruption within the last 1,000 years.
Evidence of eruption or seismic signs within the last 10,000 years.
The total height and width of the volcanic cone.
The presence of snow or vegetation on the volcano's slopes.
Which type of eruption is characterized by a sustained, jet-like explosion of ash and gas that reaches the stratosphere, often forming a pillar-like column up to 45 km high?
Strombolian
Plinian
Phreatomagmatic
Effusive
The Hawaii islands are "Hotspot" volcanoes. While most volcanoes form at the edges of plates, why do these form in the middle of the Pacific Plate?
The volcanoes move together with the plate to find a new heat source.
The Pacific Plate moves over a hotspot that stays in one place.
The ocean water is heavy that it pulls the magma to the surface.
The middle of the plate is the only place where the crust is thin.
The Philippines is part of the Pacific Ring of Fire. Why do our volcanoes, like Mt. Mayon, explode more violently than the volcanoes in Hawaii?
The salt in the Philippine Sea makes the volcano much more active.
Our magma is thicker and traps more gas, causing it to explode.
Philippine volcanoes are much hotter because they are near the equator.
Philippine volcanoes are taller, so the lava has further to fall.
A tall, cone-shaped volcano with no record of eruption begins to swell and cause earthquakes. What does this tell the community?
It is an inactive cinder cone turning into a mountain.
It is a dormant shield volcano with quiet lava flows.
It is an extinct volcano and is safe to live nearby.
It is an active stratovolcano that may explode.
Analyze the following data: A volcano is located at a subduction zone. It produces light-colored, viscous (thick) rhyolitic magma. Which prediction about its physical shape and eruption style is most logical?
It will be a small, circular hole in the ground that only releases steam.
It will be a flat, wide volcano with quiet lava flows that travel long distances.
It will be a tall, steep-sided volcano with violent, ash-rich eruptions.
It will be a perfectly symmetrical cone that only erupts dark, runny basalt.
Which type of volcano has a broad, gently sloping cone formed by fluid lava flows?
Cinder cone volcano
Composite volcano
Lava dome
Shield volcano
What magma composition is mainly responsible for the steep sides of a composite volcano?
Basaltic magma
Andesitic magma
Ultramafic magma
Rhyolitic magma
Which characteristic best explains why cinder cone volcanoes have a steep cone shape?
Magma erupts quietly without explosions
Lava flows slowly and spreads widely
Loose volcanic fragments pile up near the vent
Lava hardens before reaching the surface
A volcano produces runny lava that flows far from the vent before cooling. What cone shape is most likely to form?
Steep and narrow cone
Broad and gently sloping cone
Dome-shaped cone
Irregular and jagged cone
Why are composite volcanoes usually taller than shield volcanoes?
Composite volcanoes are built from alternating lava and pyroclastic materials
Shield volcanoes have thicker lava
Composite volcanoes erupt only once
Shield volcanoes erupt more explosively
Which conclusion best explains the relationship between magma composition and volcano shape?
The viscosity of magma determines how lava builds the volcano cone
Earthquakes control the height and width of volcanoes
Volcano shape depends mainly on wind and weather conditions
All volcanoes have the same shape regardless of magma type
What condition is necessary for the formation of a typhoon?
Cold ocean water
Warm ocean water
Dry air masses
High mountain ranges
Which Ocean region is the main source of typhoons that affect the Philippines?
Southern Ocean
Western Pacific Ocean
Indian and South Pacific Ocean
Atlantic and Northeast Pacific Ocean
Why do typhoons usually weaken after making landfall?
Wind speed increases over land
They lose their heat and moisture source
They gain more moisture
Air pressure becomes lower
How does the Philippines’ location contribute to frequent typhoon occurrences?
It is located near the equator and surrounded by warm seas
It has many mountains ranges
It experiences cold ocean currents
It is far from the Pacific Ocean
Why does warm seawater play an important role in typhoon development?
It increases air pressure
It slows down cloud formation
It supplies heat and moisture that strengthen the storm
It blocks wind movement
Which situation best explains why typhoons are more common during certain months in the Philippines?
Mountains disappear during summer
Ocean temperatures become warmer during the rainy season
The Earth moves farther from the Sun
Winds completely stop blowing
Which part of a typhoon is characterized by calm weather and clear skies?
Outer Rainbands
Inner Rainbands
Eyewall
Eye
What is the main characteristic of the eyewall of a typhoon?
It is far from the storm center
It contains the strongest winds and heaviest rainfall
It has no clouds
It has weak winds and light rain
Why do coastal areas often experience storm surges during a strong typhoon?
Air pressure increases rapidly
Rainfall stops suddenly
Strong winds push seawater toward the shore
The ocean becomes colder
How does increasing wind speed affect the classification of a tropical cyclone?
It changes into a thunderstorm
It stops moving completely
It becomes weaker and smaller
It may intensify into a typhoon
What usually happens to a typhoon when it moves over a large body of warm water?
It changes direction
It becomes stronger
It slows down
It stops completely
What factor from bodies of water mainly helps a typhoon grow stronger?
Heat energy
Land friction
Mountain barriers
Surface roughness
Why do typhoons weaken after making landfall?
Land areas have less heat and moisture than oceans
Land areas have stronger winds than oceans
Land surfaces reflect sunlight back to space
Land surfaces increase air pressure rapidly
Two typhoons have the same strength over the ocean. One passes over a flat island, while the other crosses a mountainous island. Which conclusion is most accurate?
The typhoon over the mountainous island will weaken faster
The typhoon over the flat island will stop immediately
Both typhoons will strengthen at the same rate
Both typhoons will have no change in intensity
Which action should be done before a typhoon occurs?
Remove warning signs
Return to flooded areas
Prepare an emergency kit
Go outside to check damage
Which behavior is considered unsafe during a typhoon?
Walking through flooded streets
Listening to weather advisories
Staying inside sturdy buildings
Keeping emergency supplies nearby
Why is it important to wait for official announcements before going outside after a typhoon?
Typhoons usually return immediately
Rescue teams stop working afterward
Rain always continues for several days
Hazards like fallen wires and unstable structures may still be present
A family lives near a river and a typhoon warning is issued. What should they do to reduce risk?
Evacuate to higher ground as advised by authorities
Secure appliances while floodwaters enter
Stay near the river to monitor water flow
Wait until the water level rises
Which precautionary measures should individuals take to prepare for potential power outages during a typhoon?
Relying on candles as the primary source of illumination
Stockpiling perishable food items in the refrigerator
Charging electronic devices and portable power banks in advance
Leaving windows and doors open to allow natural light to enter the home
What is the recommended precautionary measure for individuals living in flood-prone areas during a typhoon?
Building additional rooms or structures at ground level to accommodate floodwater
Implementing an evacuation plan and relocating to higher ground before the onset of flooding
Constructing barriers or levees around the perimeter of the property
Purchasing flood insurance to cover potential damage to property and belongings
What is the recommended precautionary measure to protect electronic devices and appliances during a typhoon-related power outage?
Continuously using electronic devices until the power is restored
Unplugging all devices and appliances to prevent damage from power surges
Covering devices and appliances with plastic
Which statement best describes the phases of the Moon?
The repeating pattern of night and day
The monthly pattern of lunar and solar eclipses
The different shapes of the Moon as seen from Earth
The sequence of seasons the Moon causes on Earth
Which statement correctly describes the motion of the Moon?
The Moon revolves around Earth as Earth revolves around the Sun
The Moon revolves around Earth but does not rotate on its axis
The Moon revolves around the Sun as the Sun revolves around Earth
The Moon does not revolve around Earth but rotates on its axis
What would most likely happen to ocean tides if there were no Moon orbiting Earth?
A moonless Earth would make tides occur every few minutes
A moonless Earth would cause the Sun to dry the oceans
A moonless Earth would have stronger and taller tides
A moonless Earth would create weaker tides
Why does the Moon have a greater tidal effect on Earth than the Sun?
The Moon rotates faster than the Sun
The Moon is a solid and the Sun is a gas
The Moon has more mass than the Sun
The Moon is closer to Earth than the Sun
Refer to the diagram of Moon positions A, B, C, and D around Earth. Which positions produce the smallest difference between high tide and low tide (neap tides)?
C or D
B or D
B or C
A or C
On the side of Earth directly opposite the Moon, what tide is expected?
The slowest moving tides
The fastest moving tides
High tide
Low tide
When the Sun, Earth, and Moon are aligned at new or full Moon, which tides occur and why?
No tides due to balanced gravitational forces
Spring tides due to combined gravitational pulls
Neap tides due to canceling gravitational pulls
Random tides due to changing lunar phases
