Phsyics Of The Atmosphere

Question 1

What is the SI unit of mass?

Answer 1

Kilograms

Question 2

What is the SI unit of density?

Answer 2

Kg/m^3

Question 3

Give 4 fundamental units used in aerodynamics

Answer 3

Length (meters)
Mass (kilogram)
Time (seconds)
Temperature (Kelvin)

Question 4

What is the unit of speed?

Answer 4

m/s

Question 5

What is the symbol used for speed?

Answer 5

v

Question 6

What is the change in speed over time known as?

Answer 6

Acceleration

Question 7

What is the symbol used for acceleration due to gravity?

Answer 7

g

Question 8

What is the SI unit of Acceleration?

Answer 8

m/s^2

Question 9

What is the formula for weight?

Answer 9

Weight = mass x gravity

Question 10

What is the unit of force?

Answer 10

Newtons

Question 11

What is the formula for Power?

Answer 11

Power = work done / time

Question 12

What is the unit for Work?

Answer 12

Joules

Question 13

What is the SI unit of pressure?

Answer 13

N/m^2

Question 14

What is the symbol used for static pressure?

Answer 14

p

Question 15

What is the formula for Pressure?

Answer 15

Pressure = Force / Area

Question 16

What is static pressure?

Answer 16

Pressure that acts in all directions

Question 17

What is dynamic pressure?

Answer 17

Pressure that acts in the direction of flow

Question 18

What is the symbol for dynamic pressure?

Answer 18

q

Question 19

What is the symbol for the speed of sound?

Answer 19

a

Question 20

Give the formula for the speed of sound and give the constant and variable

Answer 20

20 x sq.rt of T

20 - constant
T - variable

Question 21

What is the unit of temperature in the speed of sound?

Answer 21

Kelvin

Question 22

Why is the speed of sound less at high altitudes?

Answer 22

Lower temperature as air molecules have less energy for transfer

Question 23

Where is the position of the pressure waves if an aircraft is flying below the speed of sound?

Answer 23

Pressure waves move ahead and behind the aircraft

Question 24

What is the region called where the aircraft moves below the speed of sound?

Answer 24

Subsonic

Question 25

What is the region where the aircraft moves at the speed of sound?

Answer 25

Transonic

Question 26

Where is the position of the pressure wave if the aircraft is flying at the same speed as the speed of sound?

Answer 26

Pressure waves form closely at the front of the aircraft as it cannot escape. Pressure waves are known as shock waves

Question 27

What is the region where the aircraft is flying at a speed above the speed of sound?

Answer 27

Supersonic

Question 28

Where is the position of the pressure wave if the aircraft is flying at a speed above the speed of sound?

Answer 28

Pressure waves increase behind the aircraft and shock waves form outside the periphery

Question 29

What is Mach Number?

Answer 29

The relationship between the aircraft speed and the speed of sound

Question 30

What is the formula for Mach number?

Answer 30

Speed of aircraft / speed of sound

Question 31

What symbol is used for the Mach Number?

Answer 31

M

Question 32

What does a Mach Number = 1 mean?

Answer 32

The aircraft is flying at the speed of sound

Question 33

What is the critical mach and in which region is it found?

Answer 33

The maximum speed the aircraft can fly at without firming shock waves Found in the subsonic region just before it hits the transonic

Question 34

In which region does a Mach number of more than 1 but less than 1.3 sit?

Answer 34

Transonic

Question 35

What region would a mach number higher than 1.3 be in?

Answer 35

Supersonic

Question 36

Define atmosphere

Answer 36

The mass of the air extending upwards from the surface if the earth

Question 37

What is the lowest layer of the atmosphere known as?

Answer 37

Troposphere

Question 38

What is the boundary between the troposphere and the stratosphere?

Answer 38

Tropopause

Question 39

In which part of the atmosphere does temperature, pressure and density vary in?

Answer 39

Troposphere

Question 40

What is the standard altitude for the tropopause?

Answer 40

11km

Question 41

What is the standard temperature at the tropopause?

Answer 41

-56.5 degrees C

Question 42

By how much does the temperature decrease with altitude under standard conditions?

Answer 42

6.5 degrees/km

Question 43

What is the height of the tropopause over the north pole?

Answer 43

8km

Question 44

What is the height of the tropopause over the south pole?

Answer 44

8km

Question 45

What is the height of the tropopause over the equator?

Answer 45

16km

Question 46

What is ICAO?

Answer 46

International Civil Aviation Organisation

Question 47

By how much does the temperature increase or decrease in the stratosphere?

Answer 47

It is constant

Question 48

What is the temperature, pressure and density at standard sea level?

Answer 48

Temperature - 288K Density - 1.225 kg/m^3 Pressure - 1013.25 Pa

Question 49

What does ISA stand for?

Answer 49

International Standard Atomosphere