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What is the force of gravity found on Dorin, which is inhabited by the Keldohrs?Dorin...

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hermanator | Student, Undergraduate | eNotes Newbie

Posted April 14, 2010 at 12:21 AM via web

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What is the force of gravity found on Dorin, which is inhabited by the Keldohrs?

Dorin is a planet, found on google search engine.

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hnystrom | High School Teacher | (Level 1) Assistant Educator

Posted July 11, 2010 at 6:45 PM (Answer #1)

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The Wookiepedia reference doesn't contain enough information to calculate the force of gravity on the surface of this fictional planet.  The force of gravity, or rathr, the acceleration due to gravity on its surface is:

g=GM/R2 where G is the universal gravitiational constant, M is the planet's mass and R is its radius. 

We are given a number for its diameter but we don't know the units (miles/km/m/other?) 

 If we knew the period of its moon and the distance between the planet and the moon we could calculate the mass of the planet.  The period is the time it takes the moon to orbit around Dorin.  We could find that by equating the gravitational force between Dorin and the moon to the centripetal force on the moon:

GMm/D2 = m4pi2D/T2 where m is the mass of the moon, D is the moon-Dorin distance, and T is the period of its orbit.  This gives us

M=4pi2D3/GT2

 

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