The document discusses the properties of air and how they enable flight. It explains that: 1) Air is a mixture of gases that takes up space, has mass, expands, and can exert force when compressed. 2) These properties of air, such as differences in air pressure, create lifting forces that allow birds, balloons, kites, and airplanes to fly. 3) We utilize the properties of air in technologies like insulation, layered clothing, and tires, which rely on trapped air pockets or compression to function.

1. FLIGHT
In order to begin our unit on flight we first have to understand what
we fly in. So, What do we fly in?
•Air
How is air useful to us?
• We breathe air
• It also has many properties that are useful to us in many different
ways. We will look at these properties as we continue this lesson

2. What is Air?
• Air is a physical substance which has weight. It has molecules
which are constantly moving.
• Air pressure is created by the molecules moving around.
• Moving air has a force that will lift kites and balloons up and
down.
• Air is a mixture of different gases; oxygen, carbon dioxide and
nitrogen.
• All things that fly need air.
• Air has power to push and pull on the birds, balloons, kites and
planes.
http://www.grc.nasa.gov/WWW/K-12/UEET/StudentSite/dynamicsofflight.html#air

3. Properties of air
• First we have to understand some properties or air:
• 1) Air takes up space
• 2) Air has mass
• 3) Air expands
• 4) Air can exert force when compressed

4. How is flight possible?
• How Wings Lift the Plane
• Airplane wings are shaped to make air move faster over the top
of the wing.
• When air moves faster, the pressure of the air decreases. So
the pressure on the top of the wing is less than the pressure on
the bottom of the wing.
• The difference in pressure creates a force on the wing
that lifts the wing up into the air.
http://www.grc.nasa.gov/WWW/K-12/UEET/StudentSite/dynamicsofflight.html#air

5. How do we use the properties of air?
• Home insulation:
• Layered clothing:
Insulation has millions of tiny air pockets within their fibres or
bubbles in plastic foam insulation. These fibres and tiny
bubbles help to slow down the process of heat transmission
Insulation
http://www.flixya.com/blog/2171743/conserving-at-home-with-insulation-improvements
Two thin layers can be warmer
yet lighter than one thick layer,
because the air trapped
between layers serves
as thermal insulation.
http://en.wikipedia.org/wiki/Layered_clothing

6. How do we use the properties of air?
• Tires
Compression