What Must the New Orbital Radius Be to Increase the Period to 8T?

[cheeselover87]

Homework Statement

a satellite has a period of T and orbital radius R. If you wish to increase the period to 8T what must the new orbital radius be. (answer= 4T, I just don't know how they got it)

Homework Equations

R1 cubed/ T1 squared = R2 cubed/ T2 squared

The Attempt at a Solution

The answer i got was 8

 

[DaveC426913]

1.
2.
3.
You've got 1. so far. 2 and 3?

 

[blacknovember]

That sounds reasonable.

Check calculation again.

 

[DaveC426913]

That sounds reasonable.

Check calculation again.

Yeeeeah. I think he may have handed that assignment in by now...