What speed would a satellite have to be placed to make it into orbit?

[joe426]

Homework Statement

Homework Equations

F = G(m1m2/r²)

The Attempt at a Solution

Well the height of Mt. Everest is 8,848 m. And I'm guessing the no atmosphere and not turning on an axis is just to setup the ideal problem. But from there I don't know how to set up the equation so that the satellite is placed into orbit.

 

[gneill]

Homework Statement

Homework Equations

F = G(m1m2/r²)

The Attempt at a Solution

Well the height of Mt. Everest is 8,848 m. And I'm guessing the no atmosphere and not turning on an axis is just to setup the ideal problem. But from there I don't know how to set up the equation so that the satellite is placed into orbit.

What's the circular orbit speed for a satellite orbiting at an altitude of 8848m?

 

[joe426]

What's the circular orbit speed for a satellite orbiting at an altitude of 8848m?

I dunno. How would I find it without given mass?

 

[joe426]

I know that centrip acceleration is equal to v^2 / r. Would I set that to 0 and solve for v?

 

[gneill]

I know that centrip acceleration is equal to v^2 / r. Would I set that to 0 and solve for v?

Nope. Right formula, but the centripetal acceleration won't be zero. What acceleration will balance it to make the total come out to zero?

 

[joe426]

Nope. Right formula, but the centripetal acceleration won't be zero. What acceleration will balance it to make the total come out to zero?

94 m/s?
Not sure what you mean by, "balance it to make the total come out to zero?"

 

[gneill]

94 m/s?
Not sure what you mean by, "balance it to make the total come out to zero?"

The radius of a circular orbit must be constant (or else it wouldn't be a circle!). That means the net radially-directed acceleration (or force) must be zero. What two accelerations act to reach a balance for a circular orbit? Or in other words, what two forces are acting?