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Mission CG7 Gravitational Field Strength

 The Question

Two objects are located at different locations about two planets with distinctly different masses. Compared to location A, the acceleration of gravity value at location B is ____.

 Formula Fix

The acceleration of gravity (g) is the acceleration an object experiences when the only force acting upon it is gravity. According to Newton's universal gravitation law, its value can be predicted by the following equation:
 
g = G • Mplanet / d2

where Mplanet represents the planet's mass and d represents the distance that the object is from the planet's center.

 Minds On Time

This is a very difficult question which explores the relationship between the acceleration of gravity, the distance from a planet's center and the mass of the planet. As demonstrated by the equation in the Formula Frenzy section, the acceleration of gravity is dependent upon the Mplanet / d2 ratio. You will need to find this ratio for locations A and B. Take your time and write down the results. If one of the locations is a distance R above the planet's surface, then the separation distance (d) is 2•R. Once you have found this important ratio for both locations, you will be ready to answer the question.

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