6. Newton's Law of Gravitation says that the magnitude F of the force exerted by a body of mass m on a GmM body of mass M is F = - where G is the gravitational constant and r is the distance between the bodies. (a) Find dF/ dr and explain its mean. What does the minus sign indicate? (b) Suppose it is known that the earth attracts an object with a force that decreases at a rate of 1N/km when r =15,000 km. How fast does this force change when r= 5,000 km?

6. Newton's Law of Gravitation says that the magnitude F of the force exerted by a body of mass m on a GmM body of mass M is F = - where G is the gravitational constant and r is the distance between the bodies. (a) Find dF/ dr and explain its mean. What does the minus sign indicate? (b) Suppose it is known that the earth attracts an object with a force that decreases at a rate of 1N/km when r =15,000 km. How fast does this force change when r= 5,000 km?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter1: Getting Started

Section: Chapter Questions

Problem 54PQ

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