Calculate the period of the Earth's moon if the radius of orbit was twice the actual value of 3.9 x 10^8 m.(adsbygoogle = window.adsbygoogle || []).push({});

a. 1.13 x 10^6 s or 13 days

b. 2.3 x 10^6 s or 26 days

c. 5.14 x 10^6 s or 59 days

d. 6.85 x10^6 s or 79 days

So far I got: v=velocity; T=time; h= hieght from surface

v=?

T=?

h=?

re= 6.38 x 10^6

me= 5.97 x 10^24

G= 6.67 x 10^-11

Another question I have is, if the radius of earth is doubled but the mass remains the same what would happen to the acceleration due to gravity. Would I divide 9.80 by 2, multiply by 2, or multiply by 1/4.

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# Homework Help: Newton's Variation of Kepler's third law

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