In a float type carburetor, where is the lowest pressure found during flight in an un-supercharged engine?

In a float-type carburetor, the lowest pressure during flight in an un-supercharged engine occurs in the Venturi. The Venturi is the narrow section of the carburetor where the airflow speeds up as it passes through, which results in a drop in pressure according to Bernoulli's principle. This reduction in pressure is essential for fuel metering, as it allows fuel to be drawn from the float chamber into the airstream for proper mixing and combustion.

The Venturi not only helps to create the necessary low pressure for fuel to enter the airflow, but it also plays a crucial role in maintaining the performance of the engine at various throttle settings. By accelerating the air and decreasing pressure, the Venturi effectively ensures the right fuel-to-air ratio is achieved, allowing for optimal engine operation.

In contrast, areas such as the air intake and throttle body do not experience the same pressure drops as the Venturi, and the float chamber maintains a relatively stable pressure to ensure a consistent supply of fuel. Thus, the correct choice reflects the fundamental principle of fluid dynamics as it applies to carburetor design and function.