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Simple Machines
Excerpt from DSM Simple Machines Teacher’s Guide, © Copyright by Delta Education, a member of the School Specialty Family.
Not for resale, redistribution, or use other than classroom use without further permission.
G LO S S A RY
arm The beam or bar of a lever.
axle A shaft on which a wheel revolves.
driven gear The gear receiving the force.
driving gear The gear transmitting the force.
effort The force needed to move a load.
energy The ability to make things change.
force A push or pull on an object; measured
in newtons.
friction A force that resists motion whenever
the surfaces of two objects rub against
each other.
fulcrum The pivot point on a lever.
gear A wheel with teeth that, when meshed
with the teeth of another wheel, is able to
transmit, modify, or change the direction of
an applied force.
gear ratio The ratio of the number of rotations
of the driving gear to the driven gear.
inclined plane A simple machine consisting of
a flat surface that is slanted.
joule A unit of work; 1 joule of work is
performed when a force of 1 newton is used
to move an object a distance of 1 meter.
lever A simple machine consisting of a rigid
bar that is free to pivot on a fulcrum.
load An object that requires force to be moved
over a distance.
lubricant A substance used to reduce the
friction between two solid surfaces.
machine A mechanical device that transmits,
modifies, or changes the direction of force
in order to help people do work.
mechanical advantage The advantage created
by a machine that enables people to do
work while using less force.
mobile An assembly of delicately balanced
levers suspended from above by thread
or wire.
newton The international unit of force.
pulley A simple machine consisting of a
wheel that rotates around a stationary axle.
The outer rim of the pulley is grooved to
accommodate a rope or chain.
ramp An inclined plane.
screw A simple machine consisting of an
inclined plane wrapped around a cylinder.
simple machine A machine that requires only
the force of a human to perform work. The
six types are the lever, the wheel and axle
(including the gear), the pulley, the inclined
plane, the wedge, and the screw.
thread The inclined plane that is wrapped
around and protrudes from the shaft of
a screw.
traction The amount of friction between two
surfaces that allows one surface to travel
across another.
wedge A simple machine that consists of two
or more inclined planes positioned to form
a thin edge.
wheel A disk that turns around an axis and
transfers force to and from an axle.
work The transfer of energy resulting from
a force acting to move an object over a
distance. Work = Force × distance.
Note: The Delta Science Reader includes its
own glossary of terms.
delta science modules Simple Machines
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