Effort: force applied to a lever to overcome the load.First-class lever: lever with effort and loads located at each end, and fulcrum in the centre.Force multiplier: machine that increases the force applied for a task, such as a first-class lever.Fulcrum: point about which a lever pivots.Lever: simple machines consisting of a rigid rod that pivots about a point.Load: force that a lever is used to overcome.Mechanical advantage: ration of a load force to the effort force used by a machine.Second-class lever: lever with the fulcrum located at one end, the effort at the other and the load in the centre.Simple machines: a device that makes work easier by changing the size or direction of a force.Speed multipliers: machines that requires a small movement of an effort to produce a large movement of a load, such as a third-class lver.Third-class lever: lever with the fulcrum located at one end
Diapositiva 4
Unit 1.2:
Inclined planes: a simple machine that reduces the effort needed to lift a load by increasing the distance it acts.Pitch: distance between adjacent threads on a screw.Ramp: an inclined plane used to help lift an object.Screw: a spiral-shaped inclined plane.Wedge: a double inclined plane, such as a knife or an axe.
Diapositiva 5
Unit 1.3:
Axle: shaft on which a wheel rotatesBlock and tackle: a system of two or more pulleys using rope or cable to lift heavy objects.Driven gear: the gear that receives force from a driving gearDriving gear: the gear that supplies the force to another gear.Gear ratio: ratio of the number of teeth on the driving gear and the number of teeth on a driver gear.Gear train: a system of interconnected gears.Gears: a wheel with teeth used to turn another gear wheelPulley: a wheel with a groove over which a rope or cable can slide, used to change the direction of a force.Rim: outer edge of a wheel.Sprocket: a toothed wheel used to link onto a chain on a bicycle.Wheel: type of lever with an axle acting as its fulcrum.
