Bernoulli's equation is applicable only to......... fluids.

Answer

To determine the type of fluids to which Bernoulli's equation is applicable, we need to consider the properties of the fluid. Here’s a step-by-step solution:

### Step 1: Understand Bernoulli's Equation
Bernoulli's equation relates the pressure, potential energy, and kinetic energy of a fluid in steady flow. It is expressed as:
\[ P + \rho gh + \frac{1}{2} \rho v^2 = \text{constant} \]
where:
- \( P \) = pressure energy per unit volume
- \( \rho \) = density of the fluid
- \( g \) = acceleration due to gravity
- \( h \) = height above a reference level
- \( v \) = velocity of the fluid

### Step 2: Identify Fluid Properties
For Bernoulli's equation to be valid, the fluid must possess certain properties:
1. **Incompressible**: The density of the fluid must remain constant. If the density changes, it violates the continuity equation, which is essential for the application of Bernoulli's principle.
2. **Non-viscous**: The fluid must not exhibit viscosity, meaning there should be no internal friction between the layers of the fluid. Viscosity causes energy loss due to friction, which disrupts the energy balance that Bernoulli's equation relies on.

### Step 3: Conclusion
Based on the above properties, we conclude that Bernoulli's equation is applicable only to:
- **Incompressible and non-viscous fluids.**

### Final Answer
Bernoulli's equation is applicable only to **incompressible and non-viscous fluids**.

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