Hi(adsbygoogle = window.adsbygoogle || []).push({});

Is "orbital velocity" supposed to be the same as "rotational velocity"? it seems that a "rotation curve" is supposed to plot the rotational velocity of a star, but then some articles e.g. http://en.wikipedia.org/wiki/Galaxy_rotation_problem claim "orbital speed" is plotted.

The equation for rotational velocity seems to be in the shape of V sin(i) but the equation for orbital velocity doesn't depend on sin.

Any help will be much appreciated.

Thanks!

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Oribtal and rotational velocities

**Physics Forums | Science Articles, Homework Help, Discussion**