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The gravitational force of a star on an orbiting planet 1 is F1. Planet 2, which is twice as massive as planet 1 and orbits at three times larger distance from the star, experiences gravitational force F2.

What is the ratio F2F1? You can ignore the gravitational force between the two planets.

User Eldhopj
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1 Answer

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Answer:

ratio = 1 : 4.5

Step-by-step explanation:

If m₁ is the mass of the star and m₂ the mass of the planet, the force of gravity F₁ for planet 1 is given by:


F_1=(Gm_1m_2)/(r^2)

The force F₂:


F_2=(Gm_1(2m_2))/((3r)^2)

The ratio:


(F_2)/(F_1)=(2)/(9)

User Paulo Bueno
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