- Wheels and Levers Glossary -
- Axle: A shaft or rod on which a wheel turns (fixed or free).
- Balance: A condition in which opposing forces exactly balance or equal each other; state of equilibrium.
- Block and Tackle: A unit made up of several pulleys linked together by ropes.
- Cog: Another term for gear wheel.
- Conservation of energy: Energy can neither be created or destroyed. The energy output of a machine is equal to the energy input.
- Driver: Wheel or gear that transfers force to other wheels or gears.
- Driven gear or wheel: The wheel or gear that is moved by the force of a driver wheel or gear.
- Effort: The force (push or pull) that produces an action.
- Energy: Ability to do work.
- Force: A push or pull that makes an object move. Force equals mass times distance.
- Friction: A force that resists motion between two objects that touch - there is less friction between smooth surfaces than between rough surfaces.
- Fulcrum: The supporting point of a lever; also called a pivot.
- Gear: Toothed wheel that transmits motion from one shaft to another.
- Gears: (beveled) Alter direction of motion by 90° (e.g. a hand mixer).
- Gears: (rack and pinion) Change circular motion to linear (straight) motion (e.g. a steering column).
- Gears: (worm) Changes direction of motion by 90° and alters speed (e.g. an electric mixer).
- Idler: A gear that transmits force and motion from one gear to another.
- Lever: A bar that can rest on a pivot or support point called a fulcrum. Force or effort is applied to one place to move a load at another place.
- Mass and weight: Mass is the amount of matter that is contained in a body measured in kilograms. Weight: is the attraction of the force of gravity on that body measured in Newtons. On the Earth, a person whose mass is 50 kg has a weight of approximately 500 N.
- Mesh: To smoothly interlock the teeth of two or more gear wheels.
- Motion: Change in the position of an object (speed = rate of motion).
- Newton: Newton (N) is the force required to give a one kg mass an acceleration of one metre per second.
- Perpetual Motion: Endless motion without friction.
- Power: The rate at which work is done. Power is the product of the time the force acts, the force required and the distance a load is moved.
- Pulley: A wheel with a groove in the rim in which a rope or belt moves.
- Resistance: The force that must be overcome to produce work in a machine - also called load
- Shaft: Another term for axle.
- Work: The result of a force moving an object.
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