When the flow parameters of any given instant remain same at every point, then flow is said to be

Options

A. 1. laminar
B. 2. steady state
C. 3. turbulent
D. 4. quasistatic

Answer

To solve the question, we need to understand the definitions of different types of fluid flow. The question states that when the flow parameters of any given instant remain the same at every point, we need to identify the type of flow being described.

### Step-by-Step Solution:

1. **Identify Flow Parameters**:
- Flow parameters can include velocity, pressure, density, etc. These parameters describe the characteristics of the fluid flow at any given instant.

2. **Definition of Steady Flow**:
- A flow is said to be **steady** if the flow parameters do not change with respect to time at any given point in the fluid. This means that if you were to measure the velocity or pressure at a specific point in the fluid, it would remain constant over time.

3. **Contrast with Other Types of Flow**:
- **Laminar Flow**: In laminar flow, the fluid moves in parallel layers (laminae), and while the flow may be smooth, different layers can have different velocities due to friction. Therefore, the flow parameters are not constant across the layers.
- **Turbulent Flow**: In turbulent flow, the fluid undergoes chaotic changes in pressure and velocity, leading to fluctuations in flow parameters. Thus, it cannot be classified as steady.
- **Quasi-static Flow**: This refers to processes that occur very slowly, where the system remains close to equilibrium. However, it does not imply that the flow parameters are constant at every point.

4. **Conclusion**:
- Based on the definitions and characteristics discussed, when the flow parameters remain the same at every point in the fluid, the flow is classified as **steady state flow**.

Thus, the correct answer to the question is that the flow is said to be **steady state flow**.