Simple mechanisms
Design & Technology · Key Stage 1 · The School
Levers
A LEVER turns around a fixed point called the PIVOT. It lets a small force move a big load — scissors, a see-saw, a wheelbarrow, a spoon opening a tin. Move the pivot closer to the load and the lever gets easier to use.
Sliders and wheels
A SLIDER moves in a straight line along a track, held by guides — like a drawer. A WHEEL AND AXLE turns to move something along; the wheel turns, the axle carries it. Both change how movement travels, not how much force there is.
Hinges and linkages
A HINGE lets one part swing while the other stays put — a door, a book, a lid. A LINKAGE joins parts so that moving one moves another, sometimes in a different direction. Pop-up books are made almost entirely of levers and linkages.
Lift a heavy book straight up 10 cm: hard, short distance. Now use a ruler as a lever with a pencil as the fulcrum near the book. Press the far end down 30 cm and the book rises 10 cm — much easier, three times the distance. Force went down by roughly the factor the distance went up. The lever traded one for the other; it did not create anything.