# Question: It takes 27 days for the Moon to orbit the

It takes 27 days for the Moon to orbit the Earth in a nearly circular orbit of radius 3.80 x 105 km.

(a) Show in symbol notation that the mass of the Earth can be found using these data.

(b) Compute the Earth’s mass and com-pare with the value given inside the back cover of the book.

(a) Show in symbol notation that the mass of the Earth can be found using these data.

(b) Compute the Earth’s mass and com-pare with the value given inside the back cover of the book.

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