Interactive exploration
Machines & MotionGears and gear ratios
How do gears trade speed for turning force?
Turn once. Count what happens. Discover gear ratios, real-world uses, and why different jobs need different gears.
Machines & Motion
Follow a force. Take apart a mechanism. Make something move.
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6 matching explorations
Interactive exploration
Machines & MotionHydraulic brakes
How does a little lever stop a spinning wheel?
Squeeze a hydraulic brake. See inside the caliper, change piston sizes, and discover how pressure becomes force.
Interactive explorationMachines & MotionCar differentials and transmissions
How do driven wheels take different paths around a corner?
Follow a transparent car around a bend, open its rear axle, and discover how a differential shares motion, torque and a low-grip limit.
Interactive exploration
Machines & MotionElectric motors
How does electricity make a motor spin?
Power a motor. Reverse its direction. Add a load and watch speed, current and turning force find a new balance.
Interactive explorationMachines & MotionFour-stroke engines
How does a piston turn fuel into motion?
Open a detailed engine, turn its crank, and take the assembly apart. Follow four different jobs hidden inside two very similar-looking turns.
Interactive explorationMachines & MotionLevers, pulleys and lifting
How can a small pull lift a heavy load?
Rerig a dock crane. Pull the same length of rope, watch the crate rise, and see what you trade for an easier lift.
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Where will curiosity take us?
Body & Health7Brain & Senses4Cells, Life & Evolution2Machines & Motion6Electricity & Energy4Computers, Networks & AI6Cities & Transport3Chemistry & Materials3Earth, Weather & Climate4Space & Astronomy4Physics, Light & Sound2Math, Probability & Systems1Everyday Technology3Scientific Thinking & Big Ideas1