creating curved lines?

Hi,

I created the magnetic object which is having the magnetic field surround that. Now i want to show the field using the lines,
but i dont know how to do that. please help me if you know and tell me if any free tools available. Thank you.

While I don’t know of any free tools, Vectrosity seems to be quite a popular tool that is not too expensive…

http://starscenesoftware.com/vectrosity.html