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Ch. 3 & 4 Motion & Forces. V. Nonlinear Motion Projectile Motion Circular Motion Free-fall. A. Projectile Motion. Projectile any object thrown in the air acted upon only by gravity. follows a parabolic path called a trajectory has horizontal and vertical velocities.
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Ch. 3 & 4Motion & Forces V. Nonlinear Motion Projectile Motion Circular Motion Free-fall
A. Projectile Motion • Projectile • any object thrown in the air • acted upon only by gravity • follows a parabolic path called a trajectory • has horizontal and vertical velocities PROJECTILE MINI-LAB
A. Projectile Motion • Projectile Velocities • Horizontal and vertical velocities are independent of each other!
Horizontal Velocity depends on inertia remains constant Vertical Velocity depends on gravity accelerates downward at 9.8 m/s2 A. Projectile Motion
ConcepTest • A moving truck launches a ball vertically (relative to the truck). If the truck maintains a constant horizontal velocity after the launch, where will the ball land (ignore air resistance)? A) In front of the truck B) Behind the truck C) In the truck • C) In the truck. The horizontal velocity of the ball remains constant and is unaffected by its vertical motion. Animation from “Multimedia Physics Studios.”
B. Circular Motion • Centripetal Acceleration • acceleration toward the center of a circular path • caused by centripetal force B-BALL DEMO PLATE DEMO
B. Circular Motion • On the ground... • friction provides centripetal force
B. Circular Motion • In orbit... • gravity provides centripetal force ROUND LAB
Near-Earth Satellites Geostationary Satellites B. Circular Motion • In orbit... • Which satellites travel faster?
B. Circular Motion • Extra Credit • Use the NASA Liftoffweb site to find theInternational SpaceStation (“STATION”)in the sky this weekend. • liftoff.msfc.nasa.gov/realtime/Jpass/20/ • Write a brief description of your sighting - time, appearance, & other observations.
C. Free-Fall • Free-Fall • when an object is influenced only by the force of gravity • Weightlessness • sensation produced when an object and its surroundings are in free-fall • object is not weightless! CUP DEMO
C. Free-Fall • Weightlessness • surroundings are falling at the same rate so they don’t exert a force on the object
C. Free-Fall Space Shuttle Missions Go to Space Settlement Video Library. NASA’s KC-135 - “The Vomit Comet” Go to CNN.com. Go to NASA.
ConcepTest 1 TRUE or FALSE: An astronaut on the Space Shuttle feels weightless because there is no gravity in space. FALSE! There is gravity which is causing the Shuttle to free-fall towards the Earth. She feels weightless because she’s free-falling at the same rate.
ConcepTest 2 Describe the path of a marble as it leaves the spiral tube shown below. It will travel in a straight line since the tube is no longer exerting a net force on it.