Why do Golf balls have dimples..?

Basically, when there is a flow over some body like sphere, at some point of velocity, there is separation of the boundary layer. This results in eddies in the wake region. This increases the drag on the ball. When the dimples are present, the fluid boundary layer is in better adhesion with the ball as the flow becomes Turbulent due to dimples. If the ball is hit with a spin, these dimples scoop up the air to the rear reducing the drag even more and also generates lift force on the ball, making it to travel even more distance.





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