If x is the distance measured from the leading edge of a flat plate, the laminar boundary layer thickness varies as

Explanation:

Boundary-Layer

When a fluid of ambient velocity flows over a flat stationary plate, the bottom layer of fluid directly contacts with the solid surface and its velocity reaches zero. Due to the cohesive forces between two layers, the bottom layer offers resistance to the adjacent layer and due to this reason, the velocity gradient develops in a fluid. A thin region over a surface velocity gradient is significant, known as the boundary layer.

The Laminar boundary layer thickness for the flat plate given by Blasius equation is :

Note:

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