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 Chapter 17
Gravitation
LEARNING OBJECTIVES
In this chapter you will learn how to:
âapply Newtonâs law of gravitation
âapply the concept of gravitational field strength
âuse Keplerâs three laws of planetary motion
âapply Newtonâs law of gravitation to orbiting bodies
âunderstand how Keplerâs laws follow from Newtonâs law of gravitation and the laws of mechanics
understand the concepts of gravitational potential energy and gravitational potential
derive an expression for the total energy of a body in a gravitational field
solve problems on orbital motion
calculate the escape speed from any point in a gravitational field
recognize the effects of a frictional force (viscous drag) on a satelliteâs orbit radius and speed
GUIDING QUESTIONS
What does the law of gravitation imply for the motion of a falling apple and a celestial body?