2 verifications about Bernoulli's Principle Bernoulli's Principle ×
“Bernoulli's principle applies only to curved surfaces and cannot be applied to flat plate rudders.”
Surface curvature is not a requirement for applying Bernoulli’s principle. Fluid-mechanics sources apply Bernoulli’s equation to flat-plate flow and explain lift through pressure differences associated with the velocity field. A caveat about one curvature-based lift explanation near a sharp leading edge does not make Bernoulli’s equation inapplicable to flat-plate rudders.
“Bernoulli's principle, involving pressure differences, and Newton's third law, involving reaction forces, are two descriptions of the same underlying physical mechanism.”
Bernoulli pressure differences and Newtonian reaction forces are compatible descriptions of one aerodynamic interaction, especially in explanations of lift. Pressure forces on a wing correspond to momentum changes in the airflow. The wording is slightly imprecise because momentum change follows most directly from Newton’s second law, while the third law identifies the reciprocal forces between the wing and air.