1. Satellite Motion Monika V Sikand Ph.d Student Stevens Institute of Technology Department of Physics. Light and Life Laboratory. Hoboken.

2. OBJECTIVE Review laws of motion and gravitation Satellite motion Escape velocity Geosynchronous orbit(Telecommunication satellites)

3. Newton’s laws of motion I. Law of Inertia II. F=ma III. Action-Reaction Isaac Newton January 4, 1643 -March31,1727

5. What is Gravity?

6. Gravity is a pulling force It pulls things down towards the earth

7. Things fall because of gravity

8. Things always fall down

9. Why do people not fall off the earth?

10. Newton’s Law of Gravitation

11. Gravity holds everything and every one on the earth

12. In Space, Gravity keeps the planets moving around the sun

13. Gravity on earth and moon

14. So how can we understand orbital motion?

15. Motion of the ball on earth

16. Example

17. Earth’s curvature

18. Satellite Smaller body revolving around a larger body

19. Natural satellites Moon, planets, comet

20. Artificial satellites Weather, spy, communication

21. Escape velocity Artificial satellite in a circular orbit around earth first achieving a speed of 7900m/s. If speed greater than 7900m/s satellite has a elliptical orbit. If velocity greater than 11km/s then satellite leaves earth’s orbit and has a escape orbit. The escape orbit’s velocity is called escape velocity.

22. Figure 7-22 Satellite orbits

23. Geostationary Earth Orbit (GEO)  Orbit is synchronous with the earths rotation.  From the ground the satellite appears fixed.  Altitude is about 22,300 miles or 36,000Km.  Coverage to 40% of planet per satellite.

24. Conclusion Newton’s law of gravitation F =Gm 1 m 2 /r 2 Satellites are revolving bodies around earth. Escape velocity is the maximum velocity required to escape the earth’s orbit. Geostationary orbits are synchronized with earth’s rotation at 36000 km of height.