Question

What will be the formula of mass of the earth in terms of g, R and G ?

• A. $G \frac{R}{g}$
• B. $g \frac{R^2}{G}$
• C. $g^2\frac{R}{g}$
• D. $G \frac{g}{R}$

Answer 1

Answer: (B)

$g \frac{R^2}{G}$

Answer 2

The gravitational force (F) $= \frac{ GMm}{R^2}$ and
F= mg. Equating both the values of gravitational force, $= \frac{ GMm}{R^2} = mg \, \, \,$ or $\, \, \, M= g \frac{R^2}{G}$ ,
where M is the mass of the earth.