Vocabulary
 Machine
Machine:: any device that makes doing
work easier
 Mechanical advantage:
advantage: the # of times a
machine multiplies the input force;
 MA
MA=
= output force/ input force
 Efficiency
Efficiency:: the percentage of the input
work done on a machine that the machine
can return in output work;
 E=output work/input work ● 100
Vocabulary
 Simple machine: one of the basic
machines that makes doing work easier
1. lever
2. Inclined plane
3. Wheel and axle
4. Pulley
5. Wedge
6. Screw
Lever
 A solid bar that
rotates, or turns,
around a fixed point
(fulcrum);
Vocabulary
 Compound Machine:
Machine: a machine that is made up
of two or more simple machines
 Nanotechnology
Nanotechnology:: the science and technology of
building electronic circuits and devices from
single atoms and molecules
 Robot
Robot:: a machine that works automatically or by
remote control
 Fulcrum
Fulcrum:: a fixed point around which a lever
rotates
Inclined Plane
 A simple machine
that is a sloping
surface
1
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Wheel and axle
 A simple machine that
is a wheel attached to
a shaft, or axle
Pulley
 A wheel with a
grooved rim that turns
on an axle
Wedge
 A simple machine that has a thick end and
a thin end; used to cut, split, or pierce
objects, or hold objects together
Machines help people do work
1. Machines change the way a force is
applied
a. If a machine decreases the amount of
force needed to do the work, the
distance over which that force must be
applied increases.
Screw
 A simple machine that
is an inclined plane
wrapped around a
cylinder; used to raise
and lower weights as
well as to fasten
objects
 Input force:
force: the force exerted on a
machine.
 Output force:
force: the force exerted on an
object by a machine
 The number of times the machine
multiplies the input force is the machine’s
b. A machine can change the direction of
an applied force
mechanical advantage
2
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2. Work transfers energy
a. A machine increases the potential or
kinetic energy of an object by doing work on
it.
b. For a certain amount of work, if distance
increases, force decreases.
4. The mechanical advantage (MA) of a machine
can be calculated
(MA= Output force/Input force)
5. Modern technology uses compound machines
(machines made up of two or more simple
machines)
6. Modern technology creates new uses for
machines
a. nanotechnology (building with atoms and
molecules)
b. robots
3. Output work is always less than input
work
a. Efficiency
(output work/input work ● 100)
b. No real machine is 100 % efficient.
c. Machines lose energy due to friction
d. Machines lose energy due to air
resistance (car design, helmet design,
airplane design)
Simple Machine
2 examples of where these
machines can be found
Lever
1.
2.
Inclined Plane
1.
2.
Wheel & Axle
1.
2.
Pulley
1.
2.
Wedge
1.
2.
Screw
1.
2.
3
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