AER1: Introduction Flashcards
Define aerodynamics
The study of forces and the resulting motion of objects through air.
Define Vectors
Show magnitude AND direction, can represent forces and be used to sum a result.
What is the difference between speed and velocity
Speed is a scalar quantity , the rate at which an object is moving. Magnitude only.
Velocity is a vector quantity and is the rate and direction at which an object is moving.
Define Force and Newtons
Force is a vector quantity; direction of push/pull and magnitude (in Newtons).
1 N is the force required to give 1kg an acceleration of 1 meter per second.
Define Static Force
Static Force is a force which acts regardless of the movement of air or aircraft. E.g. Gravity
Define Dynamic Force
Dynamic Force is one that causes or is a result of the aircraft’s movement or movement of the air. E.g. Lift/Thrust/Drag.
Define Newtons Law One
An object will continue to move through space at a constant velocity until an external force is applied
Define Newtons law Two
If a force is applied to an object, it will accelerate at a rate proportional to its mass and the force applied:
F = ma
Define Newtons law Three
For every action, there is an equal and opposite reaction
Define energy
A body or object has energy when it has the capacity to do work. These are Scalar quantities (Joule). Energy cannot be created or destroyed, only manipulated in its form.
Define Kinetic Energy
Energy produced as a result of motion. Proportional to velocity
Define Potential energy
Energy that is stored by an object which has the potential for use.
Define a gas
A group of molecules that are not bonded together.
How is density of gas measured
Measured by the quantity of particles in a given volume or space and is a function of temperature and pressure.
What happens to the density of a gas if the pressure increases?
Density will also increase as more gas particles are getting pushed closer together.
What happens to the density of a gas if the temperature is increased?
The density will decrease as the particles have more kinetic energy due to the heat and will be repelling each other more.
Define Boyle’s Law
Pressure and volume of gas have an inverse relationship, when the temperature remains constant. (Volume increases, Pressure decreases and vice versa)
Define Lussac’s Law
When the volume is kept constant, temperature increases and pressure will also increase (and vice versa)
What are the four forces on an aircraft in flight?
Lift, Thrust, Weight, Drag
Define Lift
Produced by the aircraft’s wing, acts perpendicular to the relative airflow
Define weight
Caused by gravity (1G), acts through the centre of gravity of the aircraft towards the earth
Define Thrust
Produced by the power plant of the aircraft, acts through the prop/engine in the direction of flight
Define drag
Produced by the lifting action of the wing and the shape of the aircraft not producing lift. Acts opposite to the flight path.
Define total reaction
The result of all aero - dynamic forces acting on the wing or aerofoil.
Define Pressure distribution
The way pressure acts on all surfaces of the aerofoil.
