As most of you probably know, the WEP states that the intertial mass and gravitational mass of any object are equal. This principle has base in Galileo's observations, that all free-falling objects have a constant acceleration. What I would like to get clear is the order of arguments that leads to this conclusion.(adsbygoogle = window.adsbygoogle || []).push({});

My guess is that it went down like this:

We know that

[tex]F = m_i \cdot a[/tex]

We also know that

[tex]F_g = \frac{k \cdot m_g \cdot M}{r^2}[/tex]

where k is a contant yet to be determined. We then have

[tex]m_i \cdot a = m_g \cdot \frac{k \cdot M}{r^2}[/tex]

We observe that a is constant, and therefore that

[tex]m_i \propto m_g[/tex]

Finally we set k = G (gravitational constant), so that [tex]m_i = m_g[/tex]

Am I right? Is this 'the origin' of the value of G?

/Diana

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# Weak Equivalence Principle (WEP)

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