Artificial Gravity. Central Force. There is no normal or tension force affecting things in orbit. Like falling bodies that accelerate, a satellite accelerates toward the earth. Gravity is a central force. orbital velocity. centripetal acceleration. Satellite. Earth. Force on Mass.
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Central Force • There is no normal or tension force affecting things in orbit. • Like falling bodies that accelerate, a satellite accelerates toward the earth. • Gravity is a central force. orbital velocity centripetal acceleration Satellite Earth
Force on Mass • Newton’s law of acceleration applies to orbits. • Centripetal acceleration times mass is the force of gravity • The situation is the same for the satellite or any object in the satellite. Satellite or astronaut F a Earth
The net force of an object in circular orbit matches the centripetal acceleration. This is the same for a freely falling object. Velocity does not change the force or acceleration. Free Fall v Fnet a a = g Fnet = mg v Earth
Weightlessness • Objects in free fall exert no normal force. • Fnet = -ma = -mg + FN • If a = g, FN = 0 • The same is true in orbit. • Fnet = mar = Fgrav + FN • If ar = Fgrav/m, FN = 0 • Objects in orbit are weightless.
Spin the Station • A spinning station in orbit has a centripetal acceleration of its own. • Acceleration is on the inside pointing inward. • There is a corresponding centripetal force for object on the inside wall. Satellite a F
Station Gravity • The centripetal force is like an elevator accelerating upward. • Fnet = mar = FN • The net force must be due to a normal force. • Experience as weight • If rw2 = g then it matches earth’s gravity. Satellite a F
Centrifuge • A centrifuge spins to create an artificial gravity. • Liquid separation • Pilot training • Amusement rides
Gravitron • The Gravitron is an amusement ride that uses centripetal force. • Rotates at 24 rpm • Diameter is 14 m
Centripetal Correction • The spin of the earth creates a centripetal acceleration toward the axis of the earth. • The effect is like accelerating down in an elevator. • Items weigh less at the equator. a = w2r