8.1 Physics Flashcards
What is the SI system based on?
The metric system, must be used by law throughout the world
What are the fundamental units in physics/aerodynamics?
Mass
Length
Time
Temperature
What is mass measured in
Kilograms (KG)
What is the mass of 1KG defined by
A piece of platinum alloy at the office of weights, Paris.
Volume of 1L of pure water at 4 degrees Celsius
How is length measured
Meters (M)
What is light defined as
A fraction of unchangeable speed of light
What is the unit measure of temperature
Kelvin (K)
What are the 6 basic fundamental quantities
Speed Acceleration Power Pressure Force Work
What is speed
A distance an object covers over a unit of time
What is acceleration
Time change takes place
What is acceleration denoted by
M/s squared
What is speed denoted by
V (velocity)
What is acceleration due to gravity denoted by
g
What is the average acceleration due to gravity
9.81 meters/second squared
What is weight measured in
N (newtons)
What is Newton’s second law
F=MA
What is work done
An object moved over a distance
Work=NM
Work = force x distance
What is work done denoted by
Joule (j) also measured in newton meters
What is power
Work over time or more specifically
Time
How is power measured
Watts ( also n/m per second)
What is pressure
Pressure = force
——-
Area
What is pressure donated by
A small p ( measured in newton per square meter)
How is static pressure calculated
Height x density x gravity
Which way does dynamic pressure act
The direction of the flow
How is dynamic pressure calculated
1/2 density x V squared
What is dynamic pressure denoted by
Small q
What is 1 bar equal to in pascal
100,000
How is static pressure denoted for aircraft technical systems
Bar/ deca newtons per square centimetre
What is the speed of sound denoted by
a
Sound waves are the same as what
Pressure waves
Is the speed of sound higher or lower at low temperatures
Lower
What are the 3 main categories of aircraft speed
Subsonic
Transonic
Supersonic
What is the Mach number used for
Keep the pilot informed of the relationship between the speed of the aircraft and the speed of sound.
What is the equation of Mach number
Speed of sound
What is the lowest layer in the atmosphere
Troposphere
What atmospheric layer would you find rain clouds
Troposphere
What is the tropopause
The boundary layer between the troposphere and stratosphere
What is the stratosphere
Atmospheric layer above the troposphere - no rain clouds are found here
Temp does not change as altitude increases
What are the heights is the tropopause over the
- north/ south poles
- equator
- 8KM over north and south poles
- 16KM over equator
What variables can vary in the troposphere
Temperature, pressure, density
A standard atmosphere was introduced by who
ICAO
Standard altitude of tropopause above earth is?
11KM
Does temperature change at all in the tropopause
Yes, at the rate of 6.5 degrees per KM
-56.5 at height of tropopause
No temp change in stratosphere
What usually decreases with altitude
Density and pressure
What are density, temperature, pressure at sea level
Temp - 288k
Density - 1.225 kg/m cubed
Pressure - 1013.25 hecto pascal
