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in my book they are trying to derive a formula for how much energy is needed to move an object height h from the earth's surface. so large that:

dent's total work (W) spent a

to move a body with mass m from the earth to a point at distance R from the center of the earth:

[tex]W=c\cdot m\cdot M\cdot (\frac{1}{R_0}-\frac{1}{R})[/tex]

c = 6.66 * 10 ^ -11, R_0 = 6370

when R increases approaching the term 1 / R all zero, and work to keep a body from the earth's surface infinitely far into the universe can be calculated by the formula

[tex]W=c\cdot \frac{m\cdot M}{R_0}[/tex]

what I can not really understand is that work is defined as force*distance, W=F*s.

why is [tex]\frac{1}{R_0}-\frac{1}{R}=distance[/tex] and why is [tex]c\cdot m\cdot M=force[/tex]??

can someone explain to me, thanks

2) why is [tex]c\cdot m\cdot M [/tex] the same at [tex]m\cdot g\cdot R^2_0[/tex], also

[tex]c\cdot m\cdot M=m\cdot g\cdot R^2_0[/tex]

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# Homework Help: Gravitational formula help

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