9781422274774

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CHAPTER

THROWING SKYDIVI G Introduction

Don’t skydivers make their acrobatics look effortless? They look like they are surfing in the air, and those somersaults look so easy. Looks can be deceiving. A lot of physics is involved in those maneuvers. How do they do it? It’s All about Forces For skydivers to make their moves, they must know all about forces. As soon as they jump from the plane, they are in motion. Therefore, the skydivers have momentum . Two constant forces act on the skydiver: gravity is pulling the skydiver down toward Earth, and air resistance is pushing up on them. The principle of momentum says that when the net of these forces changes, so does the skydiver’s momentum. It is important to remember that every force is an interaction between two objects: not only is the air pushing on the skydiver, the skydiver is also pushing on the air.

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