What is a common application of Bernoulli's equation?

The correct answer highlights the application of Bernoulli's equation in analyzing fluid flow and pressure in pipes and ducts. Bernoulli's equation is derived from the conservation of energy principle and it describes the relationship between the velocity of a fluid, pressure, and elevation in a streamline flow. This makes it particularly useful in engineering scenarios where predicting how fluid behaves in a confined space is crucial. For instance, it can help in understanding how fluid speed changes as it flows through varying cross-sectional areas of a pipe and how that affects pressure within the system. This understanding is vital for designing efficient piping systems, optimizing flow rates, and ensuring proper fluid delivery in various applications.

The other options address different principles and applications not related to Bernoulli's equation, such as mechanical advantage in levers, heat transfer in thermal systems, and static friction, which involve different physics concepts.