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Future-Ready · Engineering

Materials & Structures

Strong structures handle FORCES — triangles and arches spread the load, and engineers pick materials by their properties.
↔️Two Big Forces: Tension & Compression
TENSION = pulling apart stretches it longer COMPRESSION = pushing together squeezes it shorter A loaded beam feels BOTH at once 🚚 TOP squeezed → compression BOTTOM stretched → tension the load pushes down; the beam pushes back
A force is a push or a pull. Every beam, rope, and bone in a structure is being pulled (tension) or pushed (compression) — usually both.
↔️ Tension (pull)
Forces try to stretch and pull apart. Ropes, cables, and a spider's web are great in tension — they're strong when pulled taut.
→← Compression (push)
Forces try to squeeze and crush together. Stone, brick, and columns are great in compression — they hold up heavy weight from above.
📐Shape Matters: Why Triangles & Arches Win
⚠️Square
🧱 it racks & leans
A four-sided frame can collapse into a slanted shape — the corners fold like a cardboard box.
😟 Wobbly & weak
✅Triangle
🧱 holds holds it can't fold!
A triangle can't change shape without breaking a side — that's why bridges use trusses made of triangles.
💪 Rigid & strong
✅Arch
🧱 load → into the ground
An arch turns the load into compression and carries it down its curve into the ground — no part gets stretched.
🏛️ Carries huge loads
🌉In Real Life: A Truss & Arch Bridge
TRIANGLE TRUSS STONE ARCH 🚗 the car's weight spreads through the triangles & down the arch into the banks
Engineers mix shapes and materials: light, strong steel triangles on top, heavy stone in the arch below — each used where its property fits best.
🔑Key Terms
💥Force A push or a pull that acts on an object. Forces try to move, bend, or break a structure.
🏋️Load The weight or force a structure has to hold up — like cars, people, snow, or wind.
↔️Tension A pulling force that stretches a material and tries to pull it apart. Cables are strong in tension.
→←Compression A squeezing force that pushes a material together. Columns and stone are strong in compression.
📐Triangle (Truss) A rigid shape that can't fold. A truss links triangles to make a strong, lightweight frame.
🏛️Arch A curved shape that turns a load into compression and carries it down into the ground.
⭐ Remember: strong structures don't fight forces — they spread the load. Triangles and arches share the push and pull so no single part gets overloaded!
✏️ Future-Ready Anchor Chart · Materials & Structures: What Makes Things Strong
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