If Kerbin had no atmosphere, what would my velocity be in 40 km circular orbit?

[THX1138]

If Kerbin had no atmosphere, what would my velocity be in a 40 km altitude circular orbit?

[oriramikad]

The equation for velocity of a satellite in circular orbit is velocity = sqrt((G*m)/r), where G is the gravitational constant, m is the mass of the body (Kerbin), and r is the height above the center of mass of Kerbin.

So the answer to your question is v = sqrt((6.673×10^{−11} * 5.2915793×10²²)/640,000) = 2348.89297 m/s.

Edited April 30, 2015 by oriramikad

[jerdrb]

You also need to acompany for the radius of the planet. That equations r is the distance between the center of mass of the first object and the second object. So idk what the radius of kerbin is but you would need to add that to 40k.

[Gaarst]

The equation for velocity of a satellite in circular orbit is velocity = sqrt((G*m)/r), where G is the gravitational constant, m is the mass of the body (Kerbin), and r is the height above the center of mass of Kerbin.

So the answer to your question is v = sqrt((6.673×10^{−11} * 5.2915793×10²²)/40,000) = 9395.57191832 m/s.

(If anything is wrong with that calculation, please correct me -- I haven't taken a formal physics class yet.)

The radius r used is not the altitude but the distance to the center of Kerbin: r = 640 000 m

EDIT: Then v = 2348.89 m/s

Edited April 30, 2015 by Gaarst

[oriramikad]

The radius r used is not the altitude but the distance to the center of Kerbin: r = 640 000 m

Thanks. Fixed.