Earth and Space Science: Earth Structure, Tectonics, Rocks, Weather and Space
What this domain covers
Grade 10 Earth and Space Science covers Earth's internal structure, the rock cycle, plate tectonics and associated hazards, weather and climate, and the solar system. PNG examples matter because the country lies in a tectonically active region.
Core rules and concepts
- Earth has a crust, mantle, liquid outer core and solid inner core. Seismic waves change speed and direction as they pass through different layers, which helps scientists infer the interior.
- Igneous rock forms when magma or lava cools. Sedimentary rock forms from compacted layers of sediment and may contain fossils. Metamorphic rock forms when existing rock is changed by heat and pressure.
- At divergent boundaries plates move apart; at convergent boundaries they collide or one subducts; at transform boundaries they slide past. Earthquakes and volcanoes concentrate at plate boundaries. PNG sits near the boundary of the Pacific and Indo-Australian plates and is part of the Ring of Fire.
- Weather is the short-term state of the atmosphere; climate is the long-term pattern. Relief rainfall occurs when moist air is forced over mountains, cools and condenses, producing rain on windward slopes.
- The planets orbit the Sun in order: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Seasons are caused by Earth's axial tilt, not by distance from the Sun.
Worked example
A map has a scale of 1:50,000. A straight road measures 4 cm on the map. Convert the scale to real distance: 4 cm x 50,000 = 200,000 cm. Since 100 cm = 1 m and 1,000 m = 1 km, 200,000 cm = 2,000 m = 2 km. The reasoning is to multiply by the scale factor first, then convert centimetres to kilometres in two steps.
Traps that cost marks
Do not say seasons are caused by Earth being closer to the Sun; the tilt of the axis is the cause. Magma is underground; lava is at the surface. Weather and climate are not interchangeable. Earthquake prediction is not reliable, so hazard preparation matters. Keep scale units consistent.