Determine the mass of the earth knowing that the mean radius of the moon’s orbit about the earth is 238,910 mi and that the moon requires 27.32 days to complete one full revolution about the earth.

Respuesta :

Answer:

Mass of the earth is [tex]6.03 \times 10^{24} kg[/tex]

Explanation:

The relationship between the orbital period, orbital radius and Mass is given by Kepler's third law

[tex]T^2=\frac{4\pi^2r^3 }{GM}[/tex]

here G is gravitational constant =[tex]6.67\times 10^{-11} Nm^2/kg^2[/tex]

M is mass of the earth

T orbital period =[tex]27.32 days= 27.32\times 24\times 3600=2360448 sec[/tex]

r is the orbital radius =[tex]238910 miles=238910\times1609.34 m=38.448\times 10^7 m[/tex]

Mass of the earth is

[tex]M=\frac{4\pi^2r^3 }{GT^2}\\M=\frac{4\pi^2(38.44\times10^7 )^3 }{6.67\times 10^{-11}(2360448)^2}\\M=6.03 \times 10^{24} kg[/tex]