23 topics · Preschool to Grade 8

How forces and simple machines work

How can a small push lift something heavy? These topics explain the forces and simple machines behind almost everything that moves. Children try levers, pulleys, ramps, wedges and screws, then see how gears, cams, belts and linkages pass motion from one part to another. They discover how springs store energy, how ball bearings cut friction, how hydraulics multiply a push and how a gyroscope stays upright. Everyday examples tie it all together: suction cups, hand pumps, siphons and caster wheels. Each topic has an animation, a part-by-part look inside, a hands-on simulation and a challenge, with words for preschool, elementary and middle school.

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23 topics in Forces & mechanisms

Forces & mechanisms

#103 Forces & mechanisms How do levers help us lift heavy objects? Move the pivot point and compare the effort needed to lift different loads.

#104 Forces & mechanisms How do pulleys make lifting easier? Thread ropes through virtual pulleys and compare pulling distance with lifting effort.

#105 Forces & mechanisms How do ramps reduce lifting effort? Change a ramp's slope and compare pushing force, travel distance, and height gained.

#106 Forces & mechanisms How do wedges split or separate materials? Push different wedge shapes into model materials and watch forces move the sides apart.

#107 Forces & mechanisms How do screw threads hold things together? Turn screws with different thread spacing and compare forward movement and fastening action.

#108 Forces & mechanisms How do gears change speed and direction? Connect different-sized gears and observe rotation speed, direction, and turning force.

#109 Forces & mechanisms How do cams create repeating movements? Rotate differently shaped cams and watch connected parts rise, pause, and fall.

#110 Forces & mechanisms How do ratchets allow movement in only one direction? Explore a toothed wheel and pawl, then build a mechanism that prevents backward movement.

#111 Forces & mechanisms How do springs store and release energy? Stretch or compress virtual springs and compare the movement produced when released.

#112 Forces & mechanisms How do ball bearings help wheels turn smoothly? Compare sliding surfaces with rolling bearings while moving the same load.

#113 Forces & mechanisms How do flywheels keep machines running smoothly? Add a flywheel to a jerky mechanism and observe changes in rotational speed.

#114 Forces & mechanisms How do mechanical linkages transfer movement? Connect pivoting bars and change their lengths to create different movements.

#115 Forces & mechanisms How do belts transfer power between wheels? Link rotating wheels with belts and investigate speed changes, tension, and slipping.

#116 Forces & mechanisms How do clutches connect and disconnect moving parts? Engage model friction plates to connect a spinning shaft to another mechanism.

#117 Forces & mechanisms How do hydraulic systems multiply force? Connect different-sized pistons with liquid and compare force with distance traveled.

#118 Forces & mechanisms How do pneumatic machines use compressed air? Route air through valves to extend and retract a model machine's piston.

#119 Forces & mechanisms How do gyroscopes help maintain orientation? Spin a virtual rotor and investigate its response when its orientation changes.

#120 Forces & mechanisms How do shock absorbers reduce bouncing? Drive over model bumps and adjust damping to control repeated bouncing.

#121 Forces & mechanisms How do suction cups stay attached? Press cups onto different surfaces and explore the pressure difference holding them in place.

#122 Forces & mechanisms How do objects stay balanced without tipping? Move weights around model objects and predict when their centers of mass cause tipping.

#178 Forces & mechanisms How does a hand pump raise water? Move a handle and follow water through a cylinder and one-way valves.

#179 Forces & mechanisms How does a siphon move water between containers? Connect virtual containers and investigate how differences in water level drive flow.

#197 Forces & mechanisms How do shopping-cart wheels swivel into position? Push a model cart and watch offset caster wheels follow changes in direction.

Keep exploring

Games to play

Machine RepairFix levers, pulleys, gears and ramps so every contraption works.
Marble MountainLay straights, curves, drops and splitters to roll marbles down the mountain.
Bridge LabBuild a bridge from beams, brace it with triangles, and stay on budget.

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