Which of the following is not based on Bernoulli`s principle?

Options

A. Laws of flotation
B. Lifting of aeroplane
C. Atomizer
D. Venturimeter

Answer

To determine which of the given options is not based on Bernoulli's principle, let's analyze each option step by step.

### Step 1: Understand Bernoulli's Principle
Bernoulli's principle states that in a flowing fluid, an increase in the fluid's speed occurs simultaneously with a decrease in pressure or potential energy. This principle is fundamental in explaining various phenomena in fluid dynamics.

### Step 2: Analyze Each Option

1. **Laws of Flotation**:
- The laws of flotation are based on Archimedes' principle, which states that an object will float if the buoyant force (upward force) acting on it is equal to the weight of the fluid displaced by the object.
- This principle does not involve the concepts of fluid speed and pressure changes as described by Bernoulli's principle.
- **Conclusion**: This option is **not based on Bernoulli's principle**.

2. **Lifting of Aeroplane**:
- The lift generated by an airplane wing is explained by Bernoulli's principle. The shape of the wing causes air to move faster over the top surface than the bottom surface, resulting in lower pressure above the wing and higher pressure below, thus creating lift.
- **Conclusion**: This option **is based on Bernoulli's principle**.

3. **Atomizer**:
- An atomizer works on the principle of Bernoulli's principle. When air is blown through the atomizer, it creates a low-pressure area that draws liquid up and disperses it as a fine mist.
- **Conclusion**: This option **is based on Bernoulli's principle**.

4. **Venturi Meter**:
- A Venturi meter is used to measure the flow rate of a fluid. It operates on Bernoulli's principle, where the fluid speed increases as it passes through a constricted section, leading to a drop in pressure.
- **Conclusion**: This option **is based on Bernoulli's principle**.

### Step 3: Final Conclusion
After analyzing all options, we find that the **Laws of Flotation** is the only option that is not based on Bernoulli's principle.

### Answer:
**The option that is not based on Bernoulli's principle is the Laws of Flotation.**

---