The Reynolds number determines: A Heat transfer rate B Whether fluid flow is laminar or turbulent (Re < 2300 laminar, Re > 4000 turbulent) C Fluid color D Fluid density ✓ Correct Answer: Option B Re = ρvD/μ. Dimensionless number comparing inertial to viscous forces. Predicts flow regime. Practice FE Exam Prep Quizzes → Browse All Questions Study Flashcards