What is a formula for velocity of a spacecraft in a circular orbit?
Also, on side note, is there a formula or I can find it from equation of motion?
What is a formula for velocity of a spacecraft in a circular orbit?
Also, on side note, is there a formula or I can find it from equation of motion?
It is $\sqrt{\frac {GM}{r}}$ , where $M$ is the mass of the body(Earth) the spacecraft is revolving around, $r$ is the distance from the center of that body(Earth), and $G$ is the universal gravitational constant.
This can be easily derived from equating centripetal acceleration and gravitational attraction, i.e. $$\frac {mv^2}{r} = \frac {GMm}{r^2}$$
Note: this is only applicable for spherical bodies.