What is torque, and why does a slow gear feel stronger?
Slower gears are stronger gears. Torque is turning strength. When gears make something slower, they also make it stronger — and when they make it faster, it gets weaker. You cannot have both for free! Tractors are slow and strong, race cars are fast.
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Hold the output axle with your fingers while turning the crank. Is it easier to stop the fast side or the slow side?
Build it: 13 builds that teach torque
- ⚖️ Balance See-Saw: A see-saw that is also a scale. Can one gear beat two? (level 1 of 5, about 12 minutes, 10 steps)
🧪 Gear Speed Lab: Two cranks, two gear pairs: one makes things FAST, one makes things STRONG. (level 2 of 5, about 20 minutes, 13 steps)- 🎡 Crank Cruiser: Turn the handle and the car rolls — every turn of your hand spins the wheels three times! (level 2 of 5, about 18 minutes, 9 steps)
🕹️ Sliding-Gear 2-Speed Cart: Your first real gearbox: slide the crank axle to switch between strong gear and fast gear! (level 2 of 5, about 22 minutes, 8 steps)- 💨 Gear-Up Speeder: The spring engine sits up high and turns a BIG gear, which spins the wheels faster! (level 2 of 5, about 25 minutes, 11 steps)
- 🐢 Pull-back Tortoise: Slow but super-strong: a spring car that can climb up a book! (level 2 of 5, about 30 minutes, 12 steps)
🏗️ Worm-Gear Crane: Crank the worm gear to lift the boom — then let go. It stays up by itself! (level 3 of 5, about 30 minutes, 15 steps)- 🏰 Castle Drawbridge: Wind the handle and the heavy bridge slowly rises — and stays up when you let go. (level 2 of 5, about 30 minutes, 15 steps)
- 🛠️ Ratchet Car Jack: Crank the handle — click, click, click — and lift a toy car. Let go and it stays up! (level 3 of 5, about 35 minutes, 15 steps)
- 🦾 XL Power Crane: The strongest motor plus a worm gear: 24 times slower and super strong. (level 4 of 5, about 35 minutes, 27 steps)
- 🧗 Worm-Drive Crawler: Super slow, super strong: worm gears drive both axles and it never rolls back. (level 4 of 5, about 50 minutes, 20 steps)
- 🚞 Cog Railway Climber: A mountain train that grips a toothed rail — it climbs super steep ramps and never slides back. (level 4 of 5, about 55 minutes, 20 steps)
- 🦾 Crank Excavator Arm: Crank the worm gears to swing the digger round and lift the boom — then dig! (level 4 of 5, about 50 minutes, 22 steps)
In the classroom
- I3 Gear Superpowers (Inventors, Intermediate)
- I5 Wheels & Measuring (Inventors, Intermediate)
- I7 Pulleys & Belts (Inventors, Intermediate)
- M1 Force, Mass & Motion (Engineers, Advanced)
Common engineering questions
How can I try torque at home?
Hold the output axle with your fingers while turning the crank. Is it easier to stop the fast side or the slow side?
Which builds teach torque?
13 MightyCog builds teach it: Balance See-Saw, Gear Speed Lab, Crank Cruiser, Sliding-Gear 2-Speed Cart and Gear-Up Speeder and more. Start with Balance See-Saw: 10 steps, about 12 minutes.