The free vortex flow forms _______

A)
parabola
B)
hyperbola
C)
concentric circles
D)
straight lines

Correct Answer :   concentric circles


Explanation : The free vortex flow is a circulatory flow of the fluid such that its stream lines are concentric circles. The velocity components for a free vortex flow are Ur and Uθ and is equal to Ur=0 and Uθ=circulation/ 2*pi*r.