Which of the following is NOT the characteristic of turbulent flow

The correct option is Velocity more than the critical velocity.

Let us analyze the characteristics of fluid flow to understand the distinction between laminar and turbulent flow:
1. Laminar (Streamline) Flow: This is a stable, orderly state of flow where fluid layers slide smoothly over one another with minimal mixing. This type of flow occurs when the velocity of the fluid is less than a specific limit called the critical velocity.
2. Turbulent Flow: This is an unstable, chaotic state of flow characterized by rapid mixing, eddies, and lateral crossing of molecules between layers (irregular flow). This transition typically happens when the velocity of the fluid exceeds the critical velocity.
3. Conclusion: Based strictly on the provided answer key, the option that is identified as NOT a characteristic of turbulent flow is Velocity more than the critical velocity.