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Fluid Density associated with Drag Force
There are three atmospheric conditions that would reduce fluid density:
(1) higher altitude
(2) lower humidity
(3) warmer temperatures

Coefficient of Drag
A measure of the surface friction between the air and the surfaces of the projectile as it moves through the air.
Coefficient of drag may be reduced by making the surface of the projectile smoother.
As long as the projectile's linear speed is less than 20 mph, making the projectile smooth is an effective method for reducing the drag.
If 20 mph or greater, it is more effective to reduce the projectile's area of drag.

Area of Drag
A measure of the area of turbulent air behind the projectile as the projectile moves through the air.
The area of drag may be reduced by making the area of turbulent air behind the projectile smaller.
(1) make the area of the projectile that collides with the air smaller
reduce height and weight of projectile
(2) change the characteristics of the projectile to create better aerodynamics
provide a smooth transition as the fluid flowing over the projectile leaves the rear end of the projectile
Both of these things cannot occur because the projectiles mainly used in sports have required dimensions or shapes.
The one exception:
If traveling at speeds 20 mph or greater, the projectile should have surfaces that have been roughened.
Example would be a golf ball.

Relative Velocity associated with Drag Force
A measure of the speed a direction of the air that is colliding with the projectile.
There is nothing that can be done to deliberately reduce relative velocity for projectile motion.
If the projectile and wind are going in the same direction, relative velocity will be lower and drag force will be smaller.
If the projectile and win are moving in opposite directions, relative velocity will be higher and drag force will be larger.

Application Time of Each External Force
For the drag force, there is nothing that can be done to reduce the application time.
If the projectile is moving, a drag force will oppose the motion and slow the body down.

Mass
An increase in the projectile's mass would decrease the effectiveness of any external force that slows the body down and result in less slowing down of the projectile.
This means the projectile will maintain a greater linear speed and would result in an increase in time in the air and an increase in horizontal distance traveled.

Fluid Density associated with Lift Force
There are three atmospheric conditions that would increase fluid density:
(1) lower altitude
(2) higher humidity
(3) colder temperatures

Relative Velocity associated with Lift Force
A measure of the speed a direction of the air that is colliding with the projectile.
There is nothing that can be done to deliberately reduce relative velocity for projectile motion.
If the projectile and wind are going in the same direction, relative velocity will be lower and lift force will be smaller.
If the projectile and win are moving in opposite directions, relative velocity will be higher and lift force will be larger.

Area of Lift
A measure of the area of the projectile that is perpendicular to the motion of the projectile as it moves through air.
The method for making the area of lift of the projectile larger is to increase the height and width of the projectile.
The projectiles we use in sport and physical activity have required dimensions. Thus, it is not possible to increase the area of lift of the projectile.

Coefficient of Lift
A measure of a projectile's ability to create life as it moves through the air.
The coefficient of lift may be increase in 3 ways:
(1) make projectile have an airfoil shape
(2) have the projectile spin
(3) increase the angle of attack as the projectile moves through the air

