How things are made.
Ten plain-English lessons across mechanical, electrical, civil, chemical, and software engineering. 200+ practice problems with worked solutions. Interactive Ohm\'s law solver, beam deflection calculator, stress and strain tools, Reynolds number, gear ratio.
Where to begin.
Ten lessons cover the whole field.
Case studies.
Famous engineers and inventors.
Key milestones in engineering.
Engineering by the numbers.
Concepts worth understanding.
Common questions, plain answers.
Engineering disciplines, side by side.
Famous engineering failures and what they taught us.
Common materials and their properties.
Open questions in engineering.
Core engineering formulas.
Lessons that teach.
Ten core engineering topics, each with worked examples and three quick practice problems. About 10 to 15 minutes per lesson. Tap any to start.
Drill the concepts.
Quick 10-question quizzes from the full question bank. Each question is explained whether you get it right or wrong.
Numbers you can play with.
Plug in real values. Ohm\'s law, stress and strain, beam deflection, Reynolds number, gear ratio, fluid pressure, RC time constant.
The workbench.
Real engineering calculators with proper math. Beam diagrams, Mohr's circle, truss solver, thermo cycles, fluid flow, electrical circuits, vibration sims, material lookups, unit converter, and more. Every tool ships with the formula it uses, the assumptions it makes, and a worked example.
Beams, stress, and strain.
Interactive shear and moment diagrams. Mohr's circle. Stress-strain curves. Truss analysis. The bread and butter of structural engineering, with diagrams that update as you change inputs.
Cycles and heat transfer.
PV diagrams for Carnot, Otto, Diesel, Brayton. Conduction, convection, radiation calculators. Heat exchangers and steam tables.
Flow, pressure, and Reynolds.
Bernoulli, pipe flow, Reynolds number, Moody-friction estimator, pump head, drag, lift. Real numbers, real answers.
Ohm to Bode.
Ohm's law, series and parallel networks, RLC transients, Bode plots, time constants, power factor.
Forces in motion.
Projectile motion, simple harmonic motion, gear trains, levers, pulleys. Animated where animation helps.
Properties of 140+ materials.
Density, modulus, yield strength, tensile strength, thermal conductivity, expansion, Poisson's ratio. Search by name or property.
| Material | ρ (kg/m³) | E (GPa) | σy (MPa) | σu (MPa) | k (W/m·K) | α (1e-6/K) | ν | Notes |
|---|
W-shapes, channels, angles.
Common structural shapes with geometric properties. Area, moment of inertia, section modulus, radius of gyration. Pick a section, get the numbers.
| Section | d (in) | bf (in) | tw (in) | tf (in) | A (in²) | Ix (in⁴) | Sx (in³) | rx (in) | Weight (lb/ft) |
|---|
Convert anything.
Length, area, volume, mass, force, pressure, energy, power, temperature, velocity, density, viscosity, torque. Engineering-grade precision.
200+ engineering formulas.
Searchable, categorized, with units and notes. Mechanics, thermo, fluids, electrical, materials, dynamics.
50 problems, every step shown.
Classic engineering problems with full solutions: given, find, formula, calculation, answer. The way your textbook should have done it.
Equilibrium analysis.
Classic FBD setups: hanging mass, inclined plane, pulley, multiple supports. Walk through each one and see the force balance equations.