Neutron STEM Lab

Engineering & STEM Calculator Directory

Browse free interactive calculators, simulations, visualizers, and reference tools by title, formula, engineering discipline, or concept. For direct one-calculation pages, see the standalone engineering calculators.

Words can be entered in any order, for example optics lens.

66 tools

Materials science visualization showing a three-dimensional crystal lattice with atoms, unit-cell edges, crystallographic directions, and a Miller plane.
Materials Scienceintermediate

3D Crystal & Molecular Lattice Viewer

Free browser-based 3D crystal and molecular lattice viewer for common materials structures and custom unit cells. Inspect SC, BCC, FCC, HCP, diamond, ionic, semiconductor, ceramic, graphene, and…

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AC Circuits: labelled diagrams and key equations for AC circuits, phasors, impedance, and RLC.
Electrical Engineeringintermediate

AC Circuits Workbench

Free AC circuit calculators for impedance, phasors, RLC circuits, resonance, real and reactive power, power factor, transformers, and frequency response.

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Acids, Bases & Equilibrium: Bases, and Equilibrium Learning Lab, showing labelled diagrams and key equations for acid base chemistry, pH, buffers, and titration.
Chemistryintermediate

Acids, Bases, and Equilibrium Learning Lab

Fourteen guided chemistry lessons that connect particles, reactions, equations, graphs, and worked reasoning for acids, bases, equilibrium, buffers, titrations, and solubility.

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Advanced Math: labelled diagrams and key equations for calculus, numerical methods, regression, and Fourier series.
Mathematicsadvanced

Advanced Mathematics Workbench

Explore numerical derivatives and integrals, interpolation, polynomial regression, Fourier series, complex numbers, partial fractions, differential equations, Taylor series, and coordinate geometry.

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Air Quality & Emissions: labelled diagrams and key equations for air quality, emissions, dispersion, and ventilation.
Environmental & Energy Engineeringintermediate

Air Quality & Emissions Workbench

Calculate emissions, control efficiency, stack flow, screening dispersion, particle settling, ventilation, and indoor-air concentrations.

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Analog Electronics: labelled diagrams and key equations for analog electronics, op amps, active filters, and amplifiers.
Electrical Engineeringintermediate

Analog Electronics Workbench

Study op-amp feedback, summing and differential stages, active filters, comparators, transistor amplifiers, instrumentation amplifiers, and oscillators.

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Atomic Structure & Diffusion: labelled diagrams and key equations for crystallography, diffusion, XRD, and defects.
Materials Scienceintermediate

Atomic Structure & Diffusion Workbench

Explore crystal structures, lattice planes, diffraction, defects, alloy density, and atomic diffusion.

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Building Energy & Efficiency: labelled diagrams and key equations for building energy, efficiency, HVAC, and insulation.
Environmental & Energy Engineeringintermediate

Building Energy & Efficiency Workbench

Estimate envelope heat transfer, insulation, infiltration, degree-day energy, HVAC, lighting, solar gains, EUI, heat recovery, and payback.

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Capacitors & Inductors: labelled diagrams and key equations for capacitors, inductors, RC circuits, and RL circuits.
Electrical Engineeringintroductory

Capacitors and Inductors Workbench

Learn electric and magnetic energy storage through capacitor and inductor networks, physical geometry, dielectrics, transients, reactance, coupling, and LC resonance.

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Pendulum Forecast Lab: labelled diagrams and key equations for chaos, nonlinear dynamics, time series, and forecasting.
Physicsadvanced

Chaotic Pendulum Forecast Lab

Integrate a two to seven arm pendulum with Runge-Kutta and race three statistical forecasters against deterministic chaos.

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Chemistry Reference: labelled diagrams and key equations for periodic table, chemistry reference, polyatomic ions, and solubility rules.
Chemistryintroductory

Chemistry Reference Center

Searchable periodic table and practical references for elements, ions, ionic formulas, solubility rules, acids and bases, activity series, VSEPR shapes, constants, and equations.

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Civil Reference Center: labelled diagrams and key equations for civil engineering reference, materials, loads, and soils.
Civil & Structural Engineeringintroductory

Civil Engineering Reference Center

Browse detailed civil and structural references for materials, loads, section properties, soils, hydraulics, surveying, structural concepts, units, and equations.

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Compressible Flow: labelled diagrams and key equations for Mach number, nozzles, shocks, and choked flow.
Fluid Mechanicsintermediate

Compressible Flow Workbench

Explore Mach number, stagnation properties, isentropic nozzles, choked flow, shocks, expansion waves, mass flux, and thrust.

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Control Simulator: a wired block diagram editor with a live scope trace.
Control Systemsintermediate

Control System Simulator

Free browser-based control system simulator with block diagrams, PID tuning, transfer functions, state-space models, step response and Bode analysis. No account or installation required.

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Control systems engineering workbench thumbnail with feedback, response, stability, frequency-response, state-space, and digital-control concepts.
Control Systemsintermediate

Control Systems Workbench

Free control systems calculators for PID tuning, transient response, stability, root locus, Bode plots, state-space methods, and digital control.

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Corrosion & Degradation: labelled diagrams and key equations for corrosion, oxidation, aging, and coatings.
Materials Scienceintermediate

Corrosion & Degradation Workbench

Explore electrochemical corrosion, oxidation, coating life, accelerated aging, fatigue damage, and environmental cracking.

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Digital Electronics: labelled diagrams and key equations for digital electronics, logic, Boolean algebra, and binary arithmetic.
Electrical Engineeringintroductory

Digital Electronics Workbench

Learn logic gates, Boolean expressions, binary arithmetic, adders, multiplexers, flip-flops, counters, timing, ADCs, DACs, and PWM.

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DIY Power System Designer thumbnail showing solar generation feeding a battery bank, inverter, AC and DC loads, and a power-flow dashboard.
Electrical Engineeringintermediate

DIY Power System Designer

Plan, simulate, document, and export a small off-grid, backup, mobile, workshop, or experimental power system from one shared load list: compare 12 V/24 V/48 V/higher-voltage DC architectures; screen…

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Dynamics & Vibration: labelled diagrams and key equations for dynamics, vibration, resonance, and balancing.
Mechanicalintermediate

Dynamics and Vibration Workbench

Eight modules covering rotational inertia, the mass-spring-damper in free and forced response, natural frequency, damping ratio from decay, shaft critical speed, two-plane rotor balancing, four-bar…

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Electrical design workbench thumbnail showing a source, conductor run, load, voltage-drop trace, and three-phase power symbol.
Electrical Engineeringintermediate

Electrical Engineering Design Workbench

Size and compare conductors, calculate voltage drop and cable loss, and solve DC, single-phase, and balanced three-phase power without jumping between reference charts.

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Component Library & Design: component selection, datasheet fields, design calculators, markings, and package guidance.
Electrical Engineeringintroductory

Electronics Component Library & Design Center

Browse major electronic component families, compare curated real parts with manufacturer datasheets, assemble guided reference circuits, and use an interactive functional circuit builder with drag…

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Energy Storage & Grid: labelled diagrams and key equations for battery, storage, grid, and microgrid.
Environmental & Energy Engineeringintermediate

Energy Storage & Grid Systems Workbench

Analyze batteries, charging, efficiency, degradation, pumped hydro, thermal and flywheel storage, peak shaving, grid losses, and microgrid balance.

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Environmental & Energy Reference: labelled diagrams and key equations for reference, environment, energy, and equations.
Environmental & Energy Engineeringintroductory

Environmental & Energy Reference Center

Search detailed environmental and energy equations, parameters, design guidance, examples, units, and limitations.

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Environmental Systems: labelled diagrams and key equations for mass balance, pollution, risk, and carbon.
Environmental & Energy Engineeringintermediate

Environmental Systems & Mass Balances Workbench

Analyze pollutant loads, mixing, retention, decay, reacting tanks, accumulation, population, screening risk, and operational carbon inventories.

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External Flow & Boundary Layers: labelled diagrams and key equations for drag, lift, boundary layers, and similarity.
Fluid Mechanicsintermediate

External Flow & Boundary Layers Workbench

Calculate drag, lift, boundary-layer growth, skin friction, sphere settling, dimensionless groups, and model similarity.

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Flight Aerodynamics: labelled diagrams and key equations for aerodynamics, flight performance, lift, and drag.
Aerospace & Rocket Scienceintermediate

Flight Aerodynamics Workbench

Free aerodynamics calculators for lift, drag, dynamic pressure, stall speed, wing loading, aircraft performance, atmosphere, and flight mechanics.

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Fluid Machinery & Systems: labelled diagrams and key equations for pumps, turbines, hydraulics, and fans.
Fluid Mechanicsintermediate

Fluid Machinery & Hydraulic Systems Workbench

Analyze pumps, turbines, operating points, affinity laws, NPSH, pump combinations, cylinders, accumulators, and fans.

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Fluid Mechanics Reference: labelled diagrams and key equations for reference, properties, equations, and measurement.
Fluid Mechanicsintroductory

Fluid Mechanics Reference Center

Browse detailed fluid properties, dimensionless numbers, equations, devices, measurement methods, modeling guidance, and limitations.

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Fluid Properties & Hydrostatics: labelled diagrams and key equations for density, pressure, buoyancy, and viscosity.
Fluid Mechanicsintermediate

Fluid Properties & Hydrostatics Workbench

Calculate density, pressure, hydrostatic forces, buoyancy, floating stability, capillarity, compressibility, and viscous shear.

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Functional Materials: labelled diagrams and key equations for thermal properties, electrical properties, dielectrics, and magnetism.
Materials Scienceintermediate

Functional Materials Workbench

Explore thermal, electrical, dielectric, magnetic, thermoelectric, and optical material properties.

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General Chemistry: labelled diagrams and key equations for general chemistry, stoichiometry, molar mass, and gas laws.
Chemistryintroductory

General Chemistry Workbench

Sixteen calculators and visual models for atoms, formulas, reactions, gases, solutions, acids and bases, equilibrium, energy, kinetics, electronic structure, geometry, and nuclear decay.

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Math Workbench: labelled diagrams and key equations for calculator, algebra, vectors, and matrices.
Mathematicsintroductory

General Mathematics Workbench

Use a scientific calculator, graph functions, solve quadratics, work with vectors and matrices, and handle significant figures, percentages, ratios, and scientific notation.

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Geometrical Optics: labelled diagrams and key equations for refraction, lenses, mirrors, and prisms.
Optics & Photonicsintroductory

Geometrical Optics Workbench

Free optics calculators and visualizers for thin lenses, mirrors, Snell’s law, refraction, critical angle, magnification, ray diagrams, and imaging systems.

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Geotechnical & Foundations: labelled diagrams and key equations for soil mechanics, foundations, earth pressure, and settlement.
Civil & Structural Engineeringintermediate

Geotechnical & Foundations Workbench

Free geotechnical engineering calculators for effective stress, soil relationships, bearing capacity, foundations, earth pressure, settlement, and site analysis.

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Hydraulics & Stormwater: labelled diagrams and key equations for hydraulics, stormwater, pipes, and open channels.
Civil & Structural Engineeringintermediate

Hydraulics & Stormwater Workbench

Calculate continuity, hydraulic head, Reynolds number, pipe losses, open-channel flow, pump power, orifice and weir discharge, and Rational Method runoff.

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Internal Pipe Flow: labelled diagrams and key equations for pipes, friction, head loss, and water hammer.
Fluid Mechanicsintermediate

Internal Pipe Flow Workbench

Free pipe flow calculators for Reynolds number, Darcy-Weisbach head loss, friction factor, minor losses, pipe sizing, parallel pipes, and water hammer.

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Introductory Circuits: labelled diagrams and key equations for circuits, ohms law, kirchhoff laws, and resistors.
Electrical Engineeringintroductory

Introductory Circuits Workbench

Free electrical circuit calculators for Ohm’s law, series and parallel resistors, voltage dividers, Kirchhoff analysis, power, source conversion, and basic DC circuits.

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Machine Design: labelled diagrams and key equations for machine design, gears, bearings, and shafts.
Mechanicalintermediate

Machine Design Workbench

Fifteen modules covering gear ratios and trains, spur gear geometry, belt and chain drives, bearing life, shaft sizing, keys, bolt preload, thread engagement, springs, flywheels, cam motion…

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Materials Reference: labelled diagrams and key equations for materials reference, properties, processing, and testing.
Materials Scienceintroductory

Materials Reference Center

Search detailed material classes, crystal structures, defects, processing, testing, failure modes, and units.

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Mechanical gearing illustration showing spur gears, an internal ring gear, and a planetary gear arrangement with speed and torque readouts.
Mechanicalintermediate

Mechanical Gear Train Simulator

Free browser-based mechanical gear train simulator for spur, compound, internal, and planetary gear systems. Explore speed ratio, rotation direction, torque multiplication, mesh velocity, and basic…

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Mechanical Properties & Failure: labelled diagrams and key equations for stress strain, fracture, fatigue, and creep.
Materials Scienceintermediate

Mechanical Properties & Failure Workbench

Reduce mechanical-test data and explore elasticity, hardness, fatigue, creep, fracture, and strengthening.

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Mechanics: labelled diagrams and key equations for mechanics, kinematics, forces, and energy.
Physicsintroductory

Mechanics Workbench

Fifteen mechanics calculators and simulations covering motion, forces, energy, rotation, oscillations, and gravity.

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Lens Ray Simulator: labelled diagrams and key equations for ray tracing, lenses, refraction, and optical materials.
Optics & Photonicsintermediate

Multi-Stage Lens Ray Simulator

Trace parallel rays through configurable spherical lens surfaces using Snell’s law and inspect focal behavior and spherical aberration.

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NASA Thermo Data: labelled diagrams and key equations for thermochemistry, NASA data, entropy, and Gibbs free energy.
Chemistryintermediate

NASA Glenn Thermochemical Data Explorer

Standard heat capacity, enthalpy, entropy, and Gibbs energy for 49 species from NASA’s published polynomial fits, with reaction properties and equilibrium constants across temperature.

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Open-Channel Flow: labelled diagrams and key equations for channels, Manning equation, hydraulic jump, and weirs.
Fluid Mechanicsintermediate

Open-Channel Flow Workbench

Free open-channel flow calculators for Manning discharge, normal depth, critical depth, specific energy, hydraulic jumps, and channel geometry.

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Orbital mechanics trajectory visualization with spacecraft orbit, central body, transfer geometry, and orbital parameters.
Aerospace & Rocket Scienceintermediate

Orbital Mechanics Simulator

Free browser-based orbital mechanics simulator for propagating spacecraft trajectories around Earth, the Moon, Mars, Jupiter, the Sun, or a custom central body.

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Orbital Mechanics: labelled diagrams and key equations for orbital mechanics, spaceflight, Hohmann transfer, and rendezvous.
Aerospace & Rocket Scienceintermediate

Orbital Mechanics Workbench

Free orbital mechanics calculators for orbital velocity, period, vis-viva, Hohmann transfer, plane changes, rendezvous, escape energy, J2 precession, and synchronous orbits.

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Organic Chemistry: labelled diagrams and key equations for organic chemistry, functional groups, IUPAC naming, and stereochemistry.
Chemistryintermediate

Organic Chemistry Workbench

Twelve guided modules for functional groups, nomenclature, molecular formulas, stereochemistry, conformations, acidity, mechanisms, reactions, spectroscopy, aromaticity, polymers, and chromatography.

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Phase Diagrams & Heat Treatment: labelled diagrams and key equations for phase diagrams, heat treatment, steel, and grain growth.
Materials Scienceintermediate

Phase Diagrams & Heat Treatment Workbench

Explore phase fractions, transformations, grain growth, case depth, tempering, and hardenability.

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Photonics: labelled diagrams and key equations for photons, lasers, fiber optics, and photodetectors.
Optics & Photonicsintermediate

Photonics Workbench

Calculate photon energy, Gaussian beam propagation, fiber modes and link budgets, photodetector response, attenuation, optical cavities, and pulsed-laser quantities.

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Polymers & Composites: labelled diagrams and key equations for polymers, composites, fiber reinforcement, and glass transition.
Materials Scienceintermediate

Polymers & Composites Workbench

Explore molecular weight, glass transition, crosslinking, composite density, stiffness, CTE, and load transfer.

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Power Electronics: labelled diagrams and key equations for power electronics, DC-DC converters, buck, and boost.
Electrical Engineeringintermediate

Power Electronics Workbench

Free power electronics calculators for buck, boost, buck-boost and flyback converters, ripple, switching losses, efficiency, device stress, and thermal estimates.

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Renewable Energy Systems: labelled diagrams and key equations for solar, wind, hydro, and renewable energy.
Environmental & Energy Engineeringintermediate

Renewable Energy Systems Workbench

Estimate solar PV and thermal, wind, hydro, geothermal, biomass, annual generation, capacity factor, portfolios, and simplified LCOE.

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Rocket Engine CEA Simulator thumbnail with a rocket nozzle, chamber-to-exit flow visualization, specific impulse and equilibrium composition metrics, and performance charts.
Aerospace & Rocket Scienceadvanced

Rocket Engine CEA Simulator

Solve rocket engine performance from chemical equilibrium: adiabatic flame temperature, product composition, characteristic velocity, thrust coefficient, and specific impulse for real propellant…

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Rocket Propulsion: labelled diagrams and key equations for rocket propulsion, thrust, specific impulse, and nozzles.
Aerospace & Rocket Scienceintermediate

Rocket Propulsion Workbench

Free rocket propulsion calculators for the rocket equation, delta-v, specific impulse, thrust, mass ratio, nozzle performance, staging, and launch-vehicle analysis.

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Semiconductor Devices: labelled diagrams and key equations for electronics, semiconductors, diodes, and BJT.
Electrical Engineeringintermediate

Semiconductor Devices Workbench

Learn diode, Zener, LED, rectifier, BJT, MOSFET, transistor-switching, and semiconductor thermal behavior through guided operating-point models.

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Solid Waste & Life Cycle: labelled diagrams and key equations for solid waste, recycling, landfill, and life cycle.
Environmental & Energy Engineeringintermediate

Solid Waste & Life-Cycle Workbench

Analyze waste generation, diversion, landfill capacity, methane, energy recovery, composting, transport emissions, recycling credits, and lifecycle totals.

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Statics & Strength: labelled diagrams and key equations for statics, strength of materials, beams, and stress.
Mechanicalintermediate

Statics and Strength of Materials Workbench

Sixteen modules covering free-body diagrams, support reactions, method of joints, section properties, shear and moment diagrams, bending and shear stress, axial load, torsion, thermal stress…

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Structural Analysis: labelled diagrams and key equations for structures, beams, trusses, and stress.
Civil & Structural Engineeringintermediate

Structural Analysis Workbench

Free structural analysis calculators for beam reactions, shear force, bending moment, deflection, section properties, truss forces, Euler buckling, and combined stress.

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Member Mechanics: labelled diagrams and key equations for mechanics of materials, bending, torsion, and connections.
Civil & Structural Engineeringintermediate

Structural Member Mechanics Workbench

Calculate member stresses, deformations, torsion, thermal restraint, eccentric loading, simplified bolt and weld demands, bearing stress, and utilization.

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Surveying & Site: labelled diagrams and key equations for surveying, site development, coordinates, and curves.
Civil & Structural Engineeringintroductory

Surveying & Site Development Workbench

Calculate coordinate geometry, bearings, traverse closure, leveling, grades, curves, plan areas, earthwork volumes, station interpolation, and cross slopes.

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Thermochemistry: labelled diagrams and key equations for thermochemistry, calorimetry, enthalpy, and Hess law.
Chemistryintermediate

Thermochemistry Workbench

Guided thermochemistry lessons for calorimetry, formation enthalpy, Hess’s law, bond energies, heating curves, entropy, Gibbs energy, catalysts, fuels, and temperature corrections.

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Thermodynamics: labelled diagrams and key equations for thermodynamics, ideal gas, heat transfer, and entropy.
Physicsintermediate

Thermodynamics Workbench

Free thermodynamics calculators for ideal-gas relationships, thermodynamic processes, work and heat, cycles, efficiencies, properties, and energy balances.

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Water & Wastewater Treatment: labelled diagrams and key equations for water, wastewater, treatment, and disinfection.
Environmental & Energy Engineeringintermediate

Water & Wastewater Treatment Workbench

Calculate sedimentation, detention, BOD removal, disinfection, activated-sludge loading, SRT, oxygen, sludge, and filtration quantities.

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Wave Optics: labelled diagrams and key equations for interference, diffraction, polarization, and coherence.
Optics & Photonicsintermediate

Wave Optics Workbench

Simulate interference, diffraction, gratings, thin films, polarization, optical resolution, and coherence with unit-labeled graphs.

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Waves and Sound: labelled diagrams and key equations for waves, sound, acoustics, and Doppler effect.
Physicsintermediate

Waves and Sound Workbench

Free wave and sound calculators for wavelength, frequency, wave speed, Doppler effect, interference, standing waves, harmonics, and acoustic relationships.

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