Download Machine - skaggsclcs

CHAPTER 4: MACHINES AND
MECHANICAL SYSTEMS
4.1 Forces in Machines
Mechanical Systems and Machines

Machine: a device with moving parts that work
together to accomplish a task
 Example:


a bicycle
Machines are designed to do something useful
Machines have an input and an output
 Input:
includes everything you do to make the machine
work
 Output: what the machine will do for you
Six Types of Simple Machines
Simple Machines

Simple machine: an unpowered mechanical device
 They

work by manipulating forces
Most machines today are combinations of simple
machines
 Bicycle:

wheels and axles, levers, and gears
Complex machine: a machine with many different
simple machines put together
Mechanical Advantage

Simple machines work by changing force and
motion
 Force:

an action that has the ability to change motion
Mechanical advantage: the ratio of output force to
input force
 Remember:
input is what you do to the machine, output
is what the machine does for you
MA = Fo
Fi
Mechanical Advantage = Output
Input
Simple Machines in the Human Body




The human body is made completely of simple
machines
Joints = levers
Hips/Shoulders = ball and socket
Anything else you can think of?