Science Test Work and Machines

Work

Transfer of energy through motion

power

rate of doing work

machines

a device that changes a force

in put force {F in}

force applied TO a machine

out put force {F out}

force applied BY a machine

work input {W in}

Work done on the machine

work output {W out }

Work done by the machine

ideal machine

input work equals output work

mechanical advantage {MA}

number of times a machine multiples the effort force

Efficiency

how much work put into a machine is changed into useful output work done by the machine

simple machine

device that does work with only one movement

lever

bar that is free to pivot, or turn about a fixed point

fulcrum

fixed point

input arm

part where the input force is applied

output arm

part that exerts the output force

pully

grooved wheel with a rope or a chain running along the groove

fixed pulley

attached to something that dose not move

moveable pully

one end of rope is fixed and wheel is free to move

block and tackle

system of pulleys that combines fixed and moveable pulleys

wheel and axle

two wheels of different sizes that rotate together

gears

wheel with teeth along its circumference

inclined plane

sloping surface that reduces amount of force required to do work

screw

inclined plane wrapped in a spiral around a cylindrical part

thread

spiral ridge that runs down

wedge

inclined plane with one or two sloping sides

compound machine

combination of two or more simple machines witch operate together