Question

what is Velocity Gradient.....

Answer 1

$\huge\mathfrak{Hello!}$

$\small{Velocity\:Gradient}$

Velocity Gradient is the rate of change of velocity with respect to length.

- Velocity gradient = dv/dx

- It’s observed in the fluid flowing in a pipe in which change in velocity ‘dv’ between two layers of fluid separated by certain distance ‘dx’ is measured.

Answer 2

Well you know what velocity is.

And as for gradient it is just rate of change (with respect to distance here)

And here is the definition

The difference in velocity between adjacent layers of the fluid is known as a velocity gradient and is given by v/x, where v is the velocity difference and x is the distance between the layers. To keep one layer of fluid moving at a greater velocity than the adjacent layer, a force F is necessary, resulting in a shearing stress F/A, where A is the area of the surface in contact with the layer being moved.