Erika+Thomas

**Description** Skydiving is a thrilling experience in which a person jumps from an aircraft and free falls before deploying their parachute. In the picture above, a group of skydivers form a circle while falling at terminal velocity.
 * Physics of Skydiving**

** Force **  Two forces act on a skydiver once they leave the plane. These forces are **gravity** and **air resistance**. Gravity is the dominant force when a skydiver first jumps out of the plane. As the skydiver falls and his/her speed increases, air resistance also increases. The gravity acting on the skydiver and the air resistance continue to decrease and increase until the forces balance out and the net force is zero. It is at this point that a skydiver reaches terminal velocity. Once a skydiver opens their parachute, they begin to slow down. This causes the skydiver to reach a new, slower terminal velocity when the forces of gravity and air resistance balance out again.

**Mass** All objects, regardless of their mass, accelerate at about 10 m/s 2. However In situations in which air resistance is involved, more massive objects fall faster. This because an object will continue to accelerate to higher speeds until the amount of air resistance is equal to their weight. Therefore, more massive skydivers will accelerate to higher speeds before reaching a terminal velocity.

** Speed ** Skydivers fall accelerate at rate of about 10m/s 2 after leaving the plane.The speed of a skydiver continues to increase as they fall until they reach terminal velocity. The terminal velocity of a human is about 120 mph with arms and legs fully extended, but experienced skydivers are able to reach speeds up to 180 mph by changing the shape of their bodies to decrease air resistance.

Physic Concept Catagories: Force, Mass, Speed

References: "What is the physics involved in skydiving?" //PhysicsLink.com//. N.p., 2011. Web. 21 Dec. 2011. <[|http://www.physlink.com/education/askexperts/] [| ae536.cfm]>.

Brian, Marshall. "How Skydiving Works." //HowStuffWorks//. N.p., 2011. Web. 21 Dec. 2011. <[] >.

"Speed of a Skydiver (Terminal Velocity)." //Hypertextbook//. N.p., 2009. Web. 21 Dec. 2011. <[] >.

"Free Fall and Air Resistance." //The Physics Classroom//. N.p., 2011. Web. 21 Dec. 2011. <[] >.