Lesson Y8-U01-L01

Y8-U01-L01 The Structure of the Earth Quiz: KS3 Geography, Unit 7

20 questions

Written by Revision Ninja · Last reviewed 11 October 2026

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Lesson Y8-U01-L01, The Structure of the Earth: 20 multiple choice questions for the KS3 Geography (National Curriculum), Unit 7: Year 8: Restless Earth: Tectonic Hazards, written with Revision Ninja.

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The 20 questions

  1. Which layer of the Earth do we live on?

    • The mantle
    • The inner core
    • The outer core
    • The crust

  2. What is the outer core made of?

    • Liquid iron and nickel
    • Solid granite and basalt
    • Liquid water and dissolved salt
    • Solid ice and frozen gases

  3. What is the mantle?

    • The thin, cool layer of soil on top of the crust
    • A liquid layer of molten iron at the centre, which is a thin skin of cooled rock on the surface
    • The thick layer below the crust, made of solid rock that can flow very slowly
    • The hottest solid metal at the centre of the Earth

  4. Which layer of the Earth is the hottest?

    • The mantle
    • The inner core
    • The outer core
    • The crust

  5. What is a tectonic plate?

    • A flat sheet of ice that covers the polar seas and stays frozen all year round
    • A giant piece of the Earth's cracked surface that slowly moves
    • A thin shell of water on the surface of the crust
    • A layer of rock in the mantle that never moves

  6. What is a convection current?

    • A cold current of water that flows along the sea floor
    • A fast wind that blows across the surface of the ocean and pushes the waves onto the land
    • Heat rising and sinking in the mantle, moving rock in slow circles
    • A stream of lava that flows down the side of a volcano

  7. What is the approximate thickness of the crust?

    • About 5 to 70 km
    • About 0.5 to 7 km
    • About 1,000 to 2,000 km
    • About 500 to 700 km

  8. What is the approximate temperature of the inner core?

    • About 150°C
    • About 25,000°C
    • About 1,000°C
    • About 5,500°C

  9. The deepest hole ever drilled reached only 12 km. Why can this hole not reveal what the core is like?

    • Holes can only be drilled through water, not solid rock
    • Drilling only reaches the mantle, which is always liquid
    • The hole was too hot to drill any deeper than 12 km, so the drill had to stop at the surface
    • The core is more than 6,000 km down, so the hole only reaches the outer crust

  10. A volcano erupts melted rock. What does this show about the layer below the crust?

    • It is cool and solid, with no heat at all
    • It is made of water that boils at the surface
    • It is a thin layer that contains no rock and is made only of water and ice
    • It is extremely hot, and rock there can melt and flow

  11. A pupil says the mantle is liquid. Which response is correct?

    • No, the mantle is solid rock that flows very slowly over millions of years
    • No, the mantle is cool and never moves at all, so it cannot carry heat from the core
    • Yes, the mantle is a liquid that flows quickly across the crust
    • Yes, the mantle is molten iron like the outer core

  12. Which process moves the tectonic plates above the mantle?

    • The gravity of the Moon pulling the plates sideways across the surface of the Earth
    • Sunlight heating the sea floor and lifting the plates
    • Convection currents that drag the plates as the rock circulates
    • The cold water of the oceans pushing the plates upward

  13. Hot soup rises, cools at the top, and then sinks again. Which part of the Earth does this analogy best describe?

    • Convection currents in the mantle
    • The solid metal of the inner core
    • The water cycle in the atmosphere
    • The thin crust that lies on top

  14. Which evidence shows that earthquake waves change at a boundary between two layers?

    • The waves speed up only on the surface of the ocean, and never change speed inside the Earth
    • The waves stop completely at the crust and never go deeper
    • The waves always travel at the same speed in every layer
    • The waves slow down or bend when they pass into a new layer

  15. Why are meteorites useful evidence about the core?

    • They are made of metals similar to those thought to be in the core
    • They are made of ice, which shows the core is cold
    • They are made of water that comes from the core and rises up through the mantle
    • They contain the same rock as the top of the crust

  16. Which order lists the layers from coolest to hottest?

    • Mantle, crust, inner core, outer core
    • Inner core, outer core, mantle, crust
    • Crust, mantle, outer core, inner core
    • Outer core, crust, inner core, mantle

  17. Why does the inner core stay solid even though it is so hot?

    • It is covered by a thick blanket of ice that keeps it solid
    • It is made of rock that does not melt at any temperature
    • It is cooler than the outer core, so it stays solid even when the pressure is very low
    • The pressure from the layers above is so great that the metal cannot melt

  18. Which statement best explains how geographers study a layer they cannot reach?

    • They rely only on written stories from ancient people, who passed down what the inside of the Earth looked like
    • They guess the structure from the colour of surface rocks
    • They use indirect evidence such as seismic waves, lava and meteorites to reach reasoned conclusions
    • They drill deeper and deeper until they reach the core

  19. Earthquake waves slow down sharply at one depth inside the Earth. What can be concluded?

    • The core is cooling and about to freeze solid, so the wave slowed down as the metal turned to ice
    • The earthquake must have been very weak at that depth
    • The waves have reached the surface of the ocean
    • A boundary exists where the material changes, so the layers differ in state or composition

  20. Why is the mantle described as solid, yet able to flow?

    • Over very long periods, the hot rock deforms slowly, behaving like an extremely thick fluid
    • It never moves, because it is cold and fixed in place
    • It flows only because of the water cycle above it, which carries the heat of the sun into the rock
    • It is actually liquid, but freezes whenever the pressure is high

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