# Sputnik's period around the earth

#### rainbowtits

1. The problem statement, all variables and given/known data
Sputnik I, the first artificial satellite to circle the planet (October 1957) had a mean orbital radius of 6953 km. Compute its period

2. Relevant equations

How do I compute the period?

3. The attempt at a solution
I thought that the radii of the sputnik could be compared to that of the moon, and same tih the period.

#### Delphi51

Homework Helper
All satellite/orbit solutions begin with
Centripetal Force = Force of gravity
Then put in the two force formulas. If you are interested in the period use the centripetal force formula that has period instead of velocity - something like F = 4(pi)mr^2/T (I probably have not remembered that exactly right!)

As usual, solve for the quantity you want to find.

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