Workin of Wind vane?

Question

Can any 1 explain me the working principle of Wind Direction vane?

Answer 1

What makes the wind vane show wind direction is the effect of the wind on two surfaces having different areas. The vane is mounted on a pivot. The surface area on one side of the pivot is larger than that on the other side. The total force on either side is a function of area and wind velocity and exposed area, Therefore, wind pushes harder on the side with the most area.