FE Other Disciplines cheat sheet

Unit conversion anchors: 1 hp = 550 ft·lbf/s = 0.7457 kW; 1 Btu = 778.17 ft·lbf = 1.055 kJ; 1 psi = 6.895 kPa; 1 gal (US) = 3.785 L = 231 in³; 1 slug = 32.174 lbm; 1 kip = 1000 lbf.

Ideal gas law forms: PV = nRT with R = 8.314 J/(mol·K) = 0.08206 L·atm/(mol·K) = 10.73 psia·ft³/(lbmol·R); specific form Pv = RT with R = R̄/M. Use absolute temperature (K or °R) in every gas relation.

Conservation of mass (steady, single stream): ṁ = ρAV = AV/v = constant. For incompressible flow through a duct, A₁V₁ = A₂V₂, so halving area doubles velocity.

First law for a steady-flow control volume: Q̇ − Ẇ = ṁ[(h₂ − h₁) + (V₂² − V₁²)/2 + g(z₂ − z₁)]. For a nozzle or diffuser, Q̇ = Ẇ = 0, so enthalpy drop converts to kinetic energy.

Bernoulli equation (steady, incompressible, frictionless along a streamline): P₁/γ + V₁²/(2g) + z₁ = P₂/γ + V₂²/(2g) + z₂, with γ = ρg. Add head-loss h_L and pump head h_p for real systems.

Reynolds number Re = ρVD/μ = VD/ν. Pipe flow transitions near Re ≈ 2300 (laminar below, turbulent above ~4000). Darcy–Weisbach head loss h_f = f(L/D)(V²/2g); f ≈ 64/Re in the laminar regime.

Statics sign conventions: ΣF = 0 and ΣM = 0 for equilibrium. A two-force member carries force only along the line joining its pins. A three-force body in equilibrium has concurrent or parallel lines of action.

Normal stress σ = F/A and axial deformation δ = FL/(AE). Shear stress τ = V/A; average shear in a bolt or pin is τ = V/A over the shear plane cross-section.

Beam bending: σ = Mc/I with c the distance from neutral axis; maximum bending moment for a simply supported beam under a central point load P is PL/4, and under uniform load w is wL²/8.

All NCEES FE exams are computer-based, closed-book, and supply an on-screen NCEES FE Reference Handbook; no personal reference material may be brought into the testing room.

The FE Other Disciplines exam is a 110-question, 6-hour computer-based exam: two sessions with a scheduled break; the afternoon session cannot be started early.

Scoring is pass/fail only; no numeric score is reported. Results are typically released within 7–10 days of the exam date.

Question format is multiple-choice with four answer options; there is no penalty for guessing, so every question should be answered.

A built-in on-screen calculator is provided; personal calculators are not permitted. Practice with the same calculator model before exam day.

Time budget: 110 questions over roughly 5 hours 20 minutes of testing time averages under 3 minutes per question; flag and skip computational time sinks, then return.

Dimensional analysis is the fastest error check: carry units through every calculation and reject any answer whose units or order of magnitude disagree.

Sanity-check results against limiting cases (zero load, zero flow, symmetric geometry) before selecting an answer; distractors are often the result of a single sign or unit slip.