Question

Giúp mình với ạ mình cần gấp ạ

Answer 1

Có:

\(m=\dfrac{F_{hd}R^2}{GM}=\dfrac{F'_{hd}\left(R+h\right)^2}{GM}\)

\(\Leftrightarrow F_{hd}R^2=F'_{hd}\left(R+h\right)^2\)

\(\Leftrightarrow45R^2=5\left(R^2+h^2+2Rh\right)\)

\(\Leftrightarrow45R^2=5R^2+5h^2+10Rh\)

\(\Leftrightarrow45R^2-5R^2-5h^2-10Rh=0\)

\(\Leftrightarrow40R^2-5h^2-10Rh=0\)

\(\Leftrightarrow h=12800km\)