Questions

Summary

1. What is air?

1.1 What is air made of?

1.2 What are the properties of air?

2. What forces are involved in flight?

2.1 2.1 How do flying devices and living things counteract gravity?

2.2 How does air movement across a surface result in lift?

2.3 How can drag be reduced?

2.4 What means of propulsion is used in aircraft?

• The forces of flight include lift, gravity, drag, and propulsion.
• Lift can be produces using Bernoulli's Principle.
• Buoyancy and lift counteract gravity.
• Thrust or propulsion act opposite to drag.
• Drag can be reduced by changing the size, shape, or smoothness of an object.
• Propulsion can be produced by various types of engines (rocket, jet, or propeller).

3. What parts are needed for things to fly?

3.1 How does a hot-air balloon fly?

3.2 What adaptations enable birds and insects to fly?

3.3 How do the parts of an aircraft stabilize and control its flight?

• The buoyancy in hot air produces lift in hot air balloons.
• Birds have specials structures and behaviours that enable them to fly.
• The control surfaces on an airplane allow control of movement in the air.