velocity
momentum = mass*velocity
acceleration
The rate at which velocity changes over time. Positive acceleration is when object are traveling at increasing velocities every second. Deceleration is when the object is slowing down over time and is simply a negative acceleration.
force=mass*acceleration
friction (drag)
gravity
motion
terminal velocity
(fluid mechanics) The velocity with which a body moves relative to a fluid when the resultant force acting on it (due to friction, gravity, and so forth) is zero.
(physics) The maximum velocity attainable, especially by a freely falling body, under given conditions. Also known as terminal speed.
From Wikipedia:
An object reaches terminal velocity when the downward force of gravity (Fg)equals the upward force of drag (Fd). The net force on the body is then zero, and the result is that the velocity of the object remains constant.
As the object accelerates (usually downwards due to gravity), the drag force acting on the object increases. At a particular speed, the drag force produced will equal the object's weight (mg). Eventually, it plummets at a constant speed called terminal velocity (also called settling velocity). Terminal velocity varies directly with the ratio of drag to weight. More drag means a lower terminal velocity, while increased weight means a higher terminal velocity. An object moving downward at greater than terminal velocity (for example because it was affected by a downward force or it fell from a thinner part of the atmosphere or it changed shape) will slow until it reaches terminal velocity.
Mathematically, terminal velocity, without considering the buoyancy effects, is given by
(see derivation)
where
Vt = terminal velocity,
m = mass of the falling object,
g = gravitational acceleration,
Cd = drag coefficient,
ρ = density of the fluid through which the object is falling, and
A = projected area of the object.
Newton’s First Law
Every body continues in its state of rest, or
of uniform motion in a right line, unless it is
compelled to change that state by forces
impressed upon it.
Objects at rest will stay at rest, and objects in motion will stay in motion in a straight line unless acted upon by an unbalanced force.
Newton’s Second Law
The change of motion is proportional to
the motive force impresses, and is made
in the direction of the right line in which
that force is impressed.
Force is equal to mass times acceleration
Newton’s Third Law
To every action there is always opposed
an equal reaction: or, the mutual action of
two bodies upon each other are always
equal, and directed to contrary parts.
For every action there is always an opposite and equal reaction.
Definition: Force
• Force is a vector quantity.
• Magnitude of the total force acting on the object is
the product of the mass and the magnitude of the
acceleration .
• Direction of the total force on a body is the direction
of the acceleration of the body.
• SI units for force are [kg-m-s-2]
• Unit has been named the Newton 1 N = 1 kg-m-s-2