Download Section 9.1

SIMPLE MACHINES 9.1
Chapter Nine: Simple Machines
9.1 Types of Simple Machines
9.2 Mechanical Advantage
9.3 Levers in the Human Body
Chapter 9.1 Learning Goals
Define machine.
Identify examples of simple
machines.
Explain the meaning of input and
output.
Investigation 9A
Levers
Key Question:
How does a lever work?
9.1 Using Machines
A machine is a device
with moving parts
that work together to
accomplish a task.
A bicycle is a good
example.
9.1 Using Machines
The input includes everything you do to
make the machine accomplish a task, like
pushing on the bicycle pedals.
The output is what the machine does for
you, like going fast or climbing a steep hill.
9.1 Forces in Machines
A simple machine is an unpowered
mechanical device, such as a lever.
9.1 Review of work
 Every process that is done by machines can
be simplified in terms of work:
1. work input: the work or energy supplied to
the process (or machine).
2. work output: the work or energy that comes
out of the process (or machine).
9.1 Review of energy
A rope and pulley
machine illustrates a
rule that is true for all
processes that
transform energy.
The total energy or
work output can never
be greater than the total
energy or work input.