2. Vocabulary
Machine: any device that makes doing
work easier
Mechanical advantage: the # of times a
machine multiplies the input force;
MA= output force/ input force
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
3. 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
4. Vocabulary
Compound Machine: a machine that is made up
of two or more simple machines
Nanotechnology: the science and technology of
building electronic circuits and devices from
single atoms and molecules
Robot: a machine that works automatically or by
remote control
Fulcrum: a fixed point around which a lever
rotates
5. Lever
A solid bar that
rotates, or turns,
around a fixed point
(fulcrum);
12. Wedge
A simple machine that has a thick end and
a thin end; used to cut, split, or pierce
objects, or hold objects together
13. 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
14. 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.
b. A machine can change the direction of
an applied force
15. Input force (effort): the force exerted on a
machine.
Output force: the force exerted on an
object by a machine
The number of times the machine
multiplies the input force is the machine’s
mechanical advantage
16. 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.
17. 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)
18. 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
19. 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.