Question

the relative velocity between two layer of water is 12 cm/s if the perpendicular distance between the layer is 1mm then velocity gradient will be
1) 1.2 per second
2) 12 per second
3) 60 per second
4) 120 per second​

Answer 1

Answer:

Velocity gradient = dv/dx

• dv = Relative velocity
• dx = Perpendicular Distance

Conversion of Distance

1mm = 0.1 cm.

So, Perpendicular Distance = 0.1 cm

=> Velocity gradient = 12/0.1

=> Velocity gradient = 120

Answer is option (4)

120 per second.

Answer 2

4. The relative velocity between two layer of water is 12 cm/s if the perpendicular distance between the layer is 1mm then velocity gradient will be 120 per second.

Given:

Relative velocity = 12cm/s.

Distance between = 1mm.

To find:

Velocity gradient = ?

Formula to be used:

Velocity gradient = $\frac{dv}{dx}$ = $\frac{120}{1} = \frac{120}{1} = 120^{-1}seconds.$

Here, dv is relative velocity between consecutive layers and dx is the perpendicular distance in the layers.

Therefore, the relative velocity between two layer of water is 12 cm/s if the perpendicular distance between the layer is 1mm then velocity gradient will be 120 per second.