# Basics

## Basic Information as SI-system, Unit converters, Physical constants

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### Acceleration Units Converter

Convert between common units of accelerations

### Acceleration of Gravity and Newton's Second Law

Acceleration of gravity and Newton's Second Law - SI and Imperial units

### Air Properties

Temperature, density, specific heat, thermal conductivity, expansion coefficient, kinematic viscosity and Prandtl's number for temperatures ranging *-150 ^{ }- 400^{ o}C*

### Angle Converter

Convert between angle units

### British Imperial System

A principal system of units

### Circles - Circumferences and Areas

Area and circumferences of circles with diameters in inches

### Conversion Chart - Inches to feet, yards and meters

Convert from inches to feet, yards and meters

### Conversion Chart - inches to mm

Convert fractional and/or decimal inches to metric mm or vice versa

### Converting Chart - U.S. Gallons to U.K. Gallons, Cubic Feet and Cubic Meters

Convert between U.S. liquid Gallons, U.K. liquid Gallons, Cubic Feet and Cubic Meters

### Decimal System Prefixes

Prefix Names of Multiples and Submultiples of Units

### Density, Specific Weight and Specific Gravity

An introduction and definition of density, specific weight and specific gravity - formulas with examples

### Drawing Scales

Scaling blueprint drawings - commonly used drawing scales

### Efficiency

Usefulnes of a process

### Empirical Equations

Empirical relationships or formulas

### Equilibrium

Mechanical, thermal, electrostatic, phase and chemical equilibrium

### Exponents - Powers and Roots

Fractional and integer exponents laws

### Flow Units Converter

Convert between volume flow units - *gpm, liter/sec, cfm, m ^{3}/h* - online flow unit converter

### Fraction-Decimal Equivalents

Inches - fractional decimal equivalents

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### Gallons of Water to Pounds

and vice versa

### Inches and Decimal Equivalents

Decimal equivalents of eights, sixteenths, thirty-seconds and sixty-fourths of an inch

### Length Units Converter

Convert between common length units like meters, feet, inches, nautical miles and many more

### Logarithms

Rules of logarithms - log_{10} and log_{e} for numbers ranging 1 to 1000

### Mass and Weight

Weight and mass - the difference

### Miscellaneous Measuring Units

Some common measuring units - gross, dozen, quire, sheets ..

### Mixtures, Solutions and Suspensions

The difference between mixtures, solutions and suspensions

### Mole and Avagadro's Number

The mole is the SI base unit for amount of substance

### Moment of Inertia

Moment of Inertia (Mass Moment of Inertia) depends on the mass of the object, its shape and its relative point of rotation - Radius of Gyration

### Natural Trigonometric Functions

Sine, Cosine and Tangent - Natural Trigonometric Functions

### Online Fuel Equivalents Calculator

Online calculator to compute the fuels equivalents - oil and gas

### Online Units Conversion Calculator

Convert Energy, Pressure, Volume, Density, Specific Volume, Specific Heat (Entropy), Enthalpy, Thermal Conductivity, Viscosity (absolute) or Coefficient of Heat Transfer units

### Ounces and Pounds converted into Grams

Converting ounces (*ozs.*) and pounds (*lbs.*) into grams (*g*)

### Physical Constants

Physical constants in SI Units

### Pressure

Introduction to pressure - relationship *psi* and *Pa*- online pressure units converter

### Pressure Units Online Converter

Convert between common pressure units like *Pa, bar, atmosphere, pound square feet, psi and more*

### Pressure to Head Unit Converter

Converting between common units for pressure and head - *lb/in ^{2}, atm, inches mercury, bars, Pa and more ..*

### Properties and State

Concept of properties and state

### Pumps, Fans and Turbines - Horsepower

Definition of British Horse Power for pumps, fans and turbines - how to convert to other common units

### Radians

The radian - a unit of angle measure - angular velocity

### Ratio and Proportion

Ratio and proportion between two quantities

### Real Numbers Algebra

Real numbers algebra - commutative law for addition, associative law for addition and more

### SI System

An introduction to the SI-system

### Solar System Constants

Sun, Earth and Moon constants

### Specific Heat Converter

Online specific heat calculator with the most common units

### Temperature

A short introduction to temperature - including Celsius, Fahrenheit, Kelvin and Rankine definitions - online temperature converter

### The Elements of the Periodic System

The elements with name, symbol, atomic number and weight

### The Periodic Table of the Elements

The periodic table of the elements with atomic numbers

### USCS - United States Customary System Units

United States Customary System Units or Imperial Units

### Unit Converter with most Common Units

Common converting units for Acceleration, Area, Density, Energy, Energy per unit mass, Force, Heat flow rate, Heat flux, Heat generation per unit volume and many more

### Vector Addition

Online vector calculator - add vectors with different magnitude and direction

### Velocity Units Converter

Convert between common velocity and speed units - with an online converter

### Volume Units Converter

Convert between common volume units like cubic meters, cubic feet, cubic inches and many more

### Volume and Surface of some Common Solids

Surface and volume of solids like rectangular prism, cylinder, pyramid, cone and sphere - online calculator

### Water - Pressure and Head

Pressure in pounds per square inch (psi) and head in feet of water (ft_{h2o})

### Water Content in Products

Products and water content before and after drying - common material like cork, grain, soap, peat, wood and more

### pH Definition

An introduction to pH

### ppm - parts per million

ppm - parts per million - is commonly used as unit of concentration