Define matter.
Any substance that occupied space and has mass.
Matter may exist in what three states?
Solid, liquid, gas
Define kinetic energy.
Kinetic energy is the energy of motion
Work is the product of what two factors?
Force and distance moved
What are the parts of a lever?
A rigid bar and a pivot point called the fulcrum
A wheelbarrow is an example of what class of lever?
A second-class lever.
Are all three states of matter affected by thermal expansion and if so, which state is affected the most?
All three states are affected, with gases being affected the most.
What is a British Thermal Unit (BTU)?
The amount of heat energy required to change the temperature of 1 pound of water 1 degree Fahrenheit.
Name the three methods of heat transfer
Conduction, convection, and radiation.
What term defines the temperature at which all molecular motion ceases?
Absolute zero
Can liquids be compressed?
No, liquids are considered incompressible
What are the customary units used to express hydraulic or pneumatic pressure in the United States?
Pounds per square inch (psi)
Describe how pressure is transmitted when a force is applied to a confined liquid.
Pressure is transmitted equally in all directions
What formula expresses the relationship between force, pressure and area?
Force equals area times pressure
What is the approximate speed of sound at sea level on a standard day?
661 knots or 340 meters per second
What is the atmospheric pressure at sea level on a standard day?
29.92 inches of Mercury or 1013.2 millibars
On a standard day at sea level, what is the value for temperature?
59 degrees F or 15 degrees C
What are the factors that determine density altitude?
Temperature and atmospheric pressure
What is the term used to describe the ratio between the amount of moisture actually present in the atmosphere as compared to the amount the air could hold if it were completely saturated?
Relative humidity
What are the four principle forces acting on an airplane in flight?
Lift, drag, thrust, and gravity
What is the term that describes the angle between the relative wind and the chord line of an airfoil?
Angle of Attack
What are the factors that cause an airplane wing to stall?
Stall is caused when the angle of attack exceeds a critical value and the airflow separates from the upper surface and becomes turbulent.
What are the principle effects that result from lowering the flaps while in flight?
Lift increases, drag increases and stall speed decreases.
What is the function of a wing mounted vortex generator?
Vortex generators delay or keep the airflow from separating from the upper surface of a wing during high speed flight.
How does blade-flapping help to compensate for dissymmetry of lift in helicopter main rotor systems?
Flapping increases the angle of attack and lift on the retreating blade and decreases the angle of attack and lift on the advancing blade.
How does the airflow through the main rotor of a helicopter change during the transition from normal flight to autorotation?
During normal flight the air moves downward and during autorotation the air moves upward (aka it reverses).
What is friction?
The opposition to relative motion between two objects in contact with each other.