The Physics of BASE Jumping
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Physics of BASE Jumping:
How does it really work?
When an object is in free fall there are very few forces acting on it. The most obvious of these is gravity, which is calculated to effect an object at a rate of 9.8 m/s/s. For an object in free fall there are four kinematic equations to describe the objects motion.
The first is an equation for/using displacement, and it goes: displacement = (initial velocity)*(time) + (1/2)*(acceleration)*(time)^2.
The Second equation used for final velocity looks like: (final velocity)^2 = (initial velocity)^2 + 2*(acceleration)*(displacement)
The Third equation can be used for final velocity is: (final velocity) = (initial velocity) + (acceleration)*(time)
The Fourth equation also for displacement is: displacement = ((initial velocity + final velocity)/2)*(time)
When an object is in free fall there are very few forces acting on it. The most obvious of these is gravity, which is calculated to effect an object at a rate of 9.8 m/s/s. For an object in free fall there are four kinematic equations to describe the objects motion.
The first is an equation for/using displacement, and it goes: displacement = (initial velocity)*(time) + (1/2)*(acceleration)*(time)^2.
The Second equation used for final velocity looks like: (final velocity)^2 = (initial velocity)^2 + 2*(acceleration)*(displacement)
The Third equation can be used for final velocity is: (final velocity) = (initial velocity) + (acceleration)*(time)
The Fourth equation also for displacement is: displacement = ((initial velocity + final velocity)/2)*(time)
http://www.physicsclassroom.com/class/1dkin/u1l6c.cfm
For wing suit flying their are other forces acting on the flyer including gravity. We look further into aerodynamics to describe the motion of wing suit jumper. The jumper increases their lift by increasing their surface area, this will result not only in decreasing their rate of falling but can be used to glide the jumper forward. A jumper's "angle of attack" is what moves them in the direction they wish to go since there is no thrust, and by bending their arms, legs, hips and even their head will help in turning directions. This force can be compared to sticking your hand out the window of a moving car, we know that sticking your hand out palm sideways will pull your arm back with a lot more force than with your palm facing down. The parachute deployment works the same way, when the parachute is opened the jumper has increased the amount of surface area exposed and will decrease their descent acceleration even more.
http://www.physicsclassroom.com/mmedia/newtlaws/sd.cfm
Another
concept to consider for the physics of base jumping is
terminal velocity. Terminal velocity is when an object
in free fall acceleration goes to
zero. This will happen when the air resistance, or the
drag, is equal to the force of gravity's acceleration, and
results in a constant velocity. A typical skydiver
will reach terminal velocity around 55m/s when they are
stretched out and not wearing a wing suit.
The formula used for calculating terminal velocity
goes: 
<---
www.processassociates.com
/process/separate/termvel.htm
Vt - Terminal Velocity p - "rho" is the density of air
m - mass A - is the cross section area that faces the wind
g - gravity Cd - is the drag coefficient (a cylinder facing down is often used as a practical substitution)
<---
www.processassociates.com
/process/separate/termvel.htmVt - Terminal Velocity p - "rho" is the density of air
m - mass A - is the cross section area that faces the wind
g - gravity Cd - is the drag coefficient (a cylinder facing down is often used as a practical substitution)