Laminar Boundary Layer Theory - Module 3

A: Option A follows the Blasius scaling for laminar flow on a flat plate and keeps units straight; the Reynolds number at 0.5 m lands comfortably below transition. Option B feels reasonable if you're thinking in terms of oil films, but it ignores the √Re dependence and undershoots by a factor of three. Option C borrows a correction from high-speed aerodynamics; at 2 m/s, compressibility doesn't move the needle. Option D mixes up roughness effects that matter after transition, not in a clean laminar regime.

A: Option A tracks the δ ~ x/√Re_x relationship; doubling velocity doubles Re_x and pulls thickness down by √2. Option B is a common first instinct when thinking in linear terms, but laminar layers don't scale that way. Option C ignores the velocity term sitting inside Reynolds number. Option D sounds physical if you're picturing turbulence, yet laminar momentum diffusion gets thinner as inertial forces rise.

A: Option A matches the symptom directly; freestream turbulence trips laminar layers early even when geometry is clean. Option B nudges Reynolds number but not by a factor of two. Option C changes the x-location of transition, not the critical Reynolds number itself. Option D creeps in from compressible flow theory, yet Mach 0.1 doesn't drive transition behavior.

A: Option A reflects how standards are applied in regulated projects; audits look for contractual compliance first, then managed change. Option B sounds defensible from a technical purity angle, but it bypasses contract law. Option C imports theory assumptions without regard to procurement terms. Option D feels pragmatic yet has no standing in either the standard or the contract.