Engineering formulas
642 formulas across nine disciplines, every one solvable for any variable it contains, in any units, with the working shown. The disciplines overlap on purpose: a mechanical engineer and a chemical engineer both want heat transfer, so it appears under both.
Mechanical 292 formulas
Statics and dynamics, stress and deflection, conduction and convection, and the pump and pipe work that moves fluid around a building. The deepest area of the site after water.
Mechanics (135)Heat Transfer (39)Fluid Mechanics (107)Strength of Materials (60)
Worked sets: The kinematic equations · The effectiveness-NTU method · The projectile motion equations · Circular and centripetal motion
Chemical & Process 204 formulas
Equilibria, kinetics and stoichiometry alongside the process side: Bernoulli, Antoine, Van der Waals, the orifice and Venturi meters, and the Rankine, Otto and Brayton cycles.
Chemistry (118)Thermodynamics (103)
Worked sets: The gas laws · Stoichiometry basics · Ways to express concentration · Colligative properties
Civil & Structural 134 formulas
Surveying and highway geometry, effective stress and bearing capacity, and structural design from the parallel axis theorem through Mohr's circle to code load combinations.
Civil & Surveying (68)Soil Mechanics (35)Strength of Materials (60)
Worked sets: Rankine earth pressure · Stress, strain and the elastic constants · Beam bending and deflection · Column buckling and slenderness
Environmental & Water 146 formulas
Treatment plant loading, disinfection, sludge and biology, plus cooling tower and boiler chemistry, and the stormwater hydrology that sizes what carries it away.
Water & Wastewater (55)Water Treatment (119)
Worked sets: The cooling tower water balance · Scaling and corrosion indices · Water hardness and softening · Chemical dosing and feed rates
Electrical 77 formulas
Circuit theory from Kirchhoff to Thevenin, and the utility side of the trade: per-unit impedance, available fault current, voltage drop, motors and filter corners.
Electricity & Magnetism (77)Electrical Trade (47)
Worked sets: The Ohm's law wheel · Reactance, resonance and time constants · Three-phase power and power factor · Motor calculations
Building Services 81 formulas
The sensible and latent air rules, duct and coil sizing, refrigeration performance, expansion tanks, and the hydronic balance that decides whether a system actually heats.
Worked sets: The pump and fan affinity laws · The HVAC heat transfer constants · Refrigeration capacity and efficiency · Duct sizing and airflow
Industrial 20 formulas
Inventory and flow, quality and capability, and the engineering economy that decides which project gets funded: EOQ, takt time, OEE, Cp and Cpk, NPV and equivalent annual cost.
Worked sets: Inventory control · Lean flow and takt · Process capability and control
Computer & Software 21 formulas
Parallel speedup, channel capacity and sampling, queueing and blocking, cache access time, reliability and availability. The arithmetic behind how fast a system can possibly go.
Worked sets: Queueing and capacity · Information and signals · Throughput and bottlenecks · Reliability and availability
Biomedical & Clinical 20 formulas
Cardiac output and haemodynamics, renal function, and pharmacokinetics from loading dose to clearance. Estimates with known limits, and the prose says where each one fails.
Worked sets: Drug dosing and pharmacokinetics · Haemodynamics and oxygen delivery · Renal function and blood chemistry
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