2 Physics Flashcards
- Define matter.
Any substance that occupies space and has mass.
- Matter may exist in what 3 states?
Solid, liquid, gas
- Define kinetic energy.
Kinetic energy is the energy of motion.
- Work is the product of what 2 factors?
Force and the 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?
2nd class lever
- Are all 3 states of matter affected by thermal expansion and if so, which state is affected most?
All 3 states are affected, gases the most.
What is a BTU?
The amount of heat energy required to change the temp of 1 pound of water 1 degree F.
- Name the 3 methods of heat transfer.
Conduction, convection, and radiation.
- What term defines the temp at which all molecular motion ceases?
Absolute zero.
- Can liquids be compressed?
No, liquids are generally considered incompressible.
- What are the customary units used to express hydraulic or pneumatic pressure in the US?
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 = area × pressure.
What is the approx speed of sound at sea level on a standard day?
661kts or 340m/s
- What is the atmospheric pressure at sea level on a standard day?
29.92 in of Mercury or 1013.2 millibars.
- On a standard day at sea level, what is the value for temp?
59 F or 15 C.
- What are the factors that determine density altitude?
Temp 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 4 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 AoA 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.
- What is friction?
The opposition to relative motion between 2 objects in contact with each other.
