Newton's version of kepler's law

[Moe_the_Genius]

Question:
Use Newton's version of Kepler's third law to find the mass of Earth. The moon is 3.9*10^(8) m away from Earth, and the moon has a period of 27.33 days.

I just have trouble with using the correct units...thanks for any help!

 

[James R]

Convert days to seconds, and your data will be in standard SI units.

 

[Andrew Mason]

Question:
Use Newton's version of Kepler's third law to find the mass of Earth. The moon is 3.9*10^(8) m away from Earth, and the moon has a period of 27.33 days.

I just have trouble with using the correct units...thanks for any help!

M_m\omega^2R = \frac{GM_eM_m}{R^2}

M_e = \frac{4\pi^2R^3}{GT^2}

T is the period in seconds. R is in metres.

AM