# Satellites in Circular Orbit

## Homework Statement

PROBLEM
What is orbital speed of 2nd satellite?
VARIABLES
• velocity of satellite 1 is 17000 meters/second
• radius of satellite 1 to center of planet is 5250000 meters
• radius of satellite 2 to planet is 8600000 m

Fc = mv2/r

? not a clue

## The Attempt at a Solution

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## Homework Equations

Fc = mv2/r
This is one of the equations you need. What force provides the centripetal force? (That will be the second relationship you'll need.)

Hint: Set up a ratio of v2 to v1

try equating gravity and centripetal force then you should be able to rearange the formula to find v?

perhaps this is right if its not i also need help on this question Alex

I figure it out.

Ouabache
Homework Helper
I figure it out.
You've got me wondering...
What is the orbital speed of the second satellite?
How did you find it?

satellite

orbital velocity,v= sqrt[gr]

v1=17000 m/s
v2=?
r1=5250000 m
r2=8600000 m

so, v2/v1=sqrt[r2 /r1]
v2=v1 * sqrt[r2/r1]