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 solve the question "Which of the following is not based on Bernoulli's principle?", we will analyze each of the options provided and determine their relation to Bernoulli's principle.

### Step-by-Step Solution:

1. **Understanding 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 fluid mechanics and is used to explain various phenomena.

2. **Analyzing Option A: Law of Flotation**:
- The law of flotation states that a floating object displaces a volume of fluid equal to its own weight. This principle is based on buoyancy, which is the upward force exerted by a fluid on an object submerged in it.
- Since buoyancy is not derived from Bernoulli's principle, option A is not based on Bernoulli's principle.

3. **Analyzing Option B: Lifting of an 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, creating a pressure difference that results in lift.
- Therefore, option B is based on Bernoulli's principle.

4. **Analyzing Option C: Atomizer**:
- An atomizer uses Bernoulli's principle to create a pressure difference. When air flows through the nozzle, it creates a low-pressure area that draws liquid up from a reservoir, atomizing it into a fine mist.
- Thus, option C is also based on Bernoulli's principle.

5. **Analyzing Option D: Venturimeter**:
- A Venturimeter is a device that measures the flow rate of a fluid. It operates on the principle of Bernoulli's equation, where a fluid's velocity increases as it passes through a constricted section of pipe, resulting in a pressure drop.
- Therefore, option D is based on Bernoulli's principle.

6. **Conclusion**:
- After analyzing all the options, we find that only **Option A: Law of Flotation** is not based on Bernoulli's principle.

### Final Answer:
**The correct answer is Option A: Law of Flotation.**