Engineering reference
Look up the number, check the assumption, move on
119 formulas with every variable and unit spelled out, 56 material property sheets, 134 convertible units and 108 rows of bolt, pipe and wire data - each with the standard behind it.
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119 items
Formulas
Equations with every variable, unit and validity condition spelled out
View allNormal Stress
Stress is force per unit area acting on a material
Normal Strain
Strain is the ratio of deformation to original length
Hooke's Law
Linear relationship between stress and strain in elastic region
Shear Stress
Average shear stress from transverse force
Torque
Torque (moment) from a perpendicular force
Moment of Inertia (Rectangle)
Second moment of area for a rectangular cross-section about centroidal axis
Moment of Inertia (Circle)
Second moment of area for a circular cross-section
Newton's Second Law
Force equals mass times acceleration
56 items
Materials
Strength, stiffness, density and thermal properties per alloy
View allAISI 1018 Carbon Steel
carbon-steel
AISI 1020 Carbon Steel
carbon-steel
AISI 1045 Carbon Steel
carbon-steel
AISI 4130 Chromoly Steel
carbon-steel
AISI 4140 Alloy Steel
carbon-steel
AISI 4340 Alloy Steel
carbon-steel
ASTM A36 Structural Steel
carbon-steel
ASTM A992 Structural Steel
carbon-steel
134 items
Units
Conversion factors across pressure, flow, torque, energy and more
View all28 items
Constants
Physical and engineering constants with their symbols and units
View allSpeed of Light in Vacuum
Exact defined value in SI. Maximum speed in universe.
Planck Constant
Exact defined value in SI. Relates photon energy to frequency.
Reduced Planck Constant
h/(2π). Common in quantum mechanics.
Elementary Charge
Exact defined value in SI. Charge of a proton.
Avogadro's Constant
Exact defined value in SI. Particles per mole.
Gravitational Constant
Universal gravitation constant. F = GMm/r².
Fine Structure Constant
Dimensionless. Characterizes electromagnetic interaction strength.
Vacuum Permittivity
Electric constant. Appears in Coulomb's law.
6 items
Disciplines
Mechanical, electrical, civil, thermal, fluids and materials
View allMechanical
Statics, dynamics, machine design, and mechanics
Electrical
Circuits, power, electromagnetics, and electronics
Civil
Structures, beams, columns, and hydraulics
Thermo
Heat transfer, cycles, and energy systems
Fluids
Fluid mechanics, pipe flow, and hydraulics
Materials
Stress, strain, material properties, and failure
17 items
Categories
The topic each formula belongs to
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