posted by anthony .
Sun will turn into a red giant star one day. Today the sun has a mass of 2*10^30kg and a radius of 70km and an angular velocity of 2.85*10^-6 rad/s.
How fast are the particles moving at the surface of the sun? When the sun turns into a red giant its mass will be 75% of what it is today and its radius will be 80 times larger calculate red giants angular velocity.
tangential velocity= radius*angularvelocity.
70km is not very far, I can drive that in about 40 minutes. I think the Sun must be larger than that.