Basic Physics Flashcards
What are the three types of heat transfer?
Conduction, convection, radiation
What is the atmospheric pressure on a standard day at sea level?
14.7 psi or 29.92 inches of mercury
How is pressure expressed in hydraulic and pneumatic‘s?
PSI
What types of matter are affected by thermal expansion?
Solid, liquid and gases
Are liquids compressible?
No
What is the basic Pascal’s law formula for computing force given pressure and area?
Force = Pressure x Area
In what direction is pressure transmitted when force is applied to a confined fluid?
Equality in all directions
What are the three states of matter?
Solid, liquid and gases
What is the term used to describe the ratio of the amount of water vapor actually present in the atmosphere as compared to when the air is saturated with water vapor?
Relative humidity
On a standard a temperature in degrees Fahrenheit, or Celsius
59°F or 15°C
What factors determine density altitude?
Pressure and atmospheric temperature
What is the approximate speed of sound on a standard day at sea level?
340 m/s or 661.7 kn.
What is the definition of friction?
Opposition to the relative movement between two objects
What does the basic lever machine consist of?
It has a rigid bar and a pivot point called the fulcrum
How does the blade flapping help compensate for the symmetry of lift in a helicopter main rotor system?
Serves to increase the angle attack and lift on the retaining blade of the rotor and decrease the angle of attack and the lift on the advancing blade side
What are the four principles forces acting on an airplane in flight?
Lift, drag, thrust and gravity
What is a British thermal unit?
The amount of heat energy required to change the temperature of 1 pound of water, 1°F
A wheelbarrow is an example of what class of lever?
A second class lever
What is the angle between the chord line of an airfoil and the direction of the relative wind called?
Angle of attack
Define matter
Any substance that occupies space and has mass
Define kinetic energy
It is the energy of motion
Work is a product of what two factors?
Force and the distance moved
What causes an airplane wing to stall?
A stall is caused by the separation of the airflow across the top of the wing from the wing upper surface, when the angle of attack exceeds a critical value
What effects do the lowering of flaps have on an airplane in flight?
Lift increases, drag increases and the stall speed decreases
What functions do wing mounted vortex generators do?
Vortx generators serve to delay or keep the airflow from separating from the upper surface of the wings during high-speed flights
What term defines the temperature at which all molecular motion ceases?
Absolute zero
What change occurs in the flow of air through the main rotor system of a helicopter when transitioning from normal flight to auto rotation?
During normal flight, the air moves downward, and during auto rotation, the air moves upward
