(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Using astronomical units as the unit of length , years as the time , and the mass of the Sun as the unit of mass , the value for k in kepler's third law is 1. In these units , what is the value of Newton's constant of gravitation G?

2. Relevant equations

P^2 =k*a^3

P^2= 4*pi^2*a^3/(G(m(1)+m(2))

Possibly k=4*pi^2/G*M(sun)

P is the period

3. The attempt at a solution

since k = 1 and k =4*pi^2/G*M(sun), all I have to do is switch variables. k=4*pi^2/(G*M(sun)) => 4*pi^2/(M(sun))=G , but I found that method to be a problem because the G I calculated isn't equal the universal Gravitational constant we are all familar with.

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# Homework Help: Kepler's third law

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