Equation Of Continuity — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Equation of Continuity Applies to the steady flow of an ideal, incompressible fluid (constant density). Assume conservation of mass: Mass entering = Mass leaving. Express mass as density volume. Express volume per unit time as Area velocity. Set density 1 A 1 v 1 = density 2 A 2 v 2. For incompressible fluids, density 1 = density 2, canceling the term to leave A 1 v 1 = A 2 v 2. Fluid must be incompressible (constant density). Flow must be steady (laminar). Pipe must be full of fluid. No sources or sinks within the control volume. Confusing flow rate (m 3/s) with flow velocity (m/s). Believing that water slows down in a narrower pipe due to friction (ignoring continuity in ideal constraints). Applying this specific form (Av=constant) to highly compressible gases without accounting for density changes.