- Physics : The study of forces and energies in space and time.
- Engineering : The profession in which a knowledge of the mathematical and natural sciences gained by study, experience and practice is applied with judgment to develop ways to economically use the materials and forces of nature for the benefit of mankind.
- Mass : The total amount of a substance, or alternatively, the total energy of a substance.
- Matter : Please do not use this term in your topic list, because there is no single article for it. Please substitute a more precise term. See Matter (disambiguation) for a list of available, more precise, topics. Please add a new usage if needed.
- Matter (chemistry) : In general chemistry, from the perspective of Newtonian mechanics, anything that occupies space and has mass.
- Density (chemistry) : A measure of the mass per unit volume of a gas, liquid or solid.
- International System of Units : Metric unit system based on the metre, kilogram, second, ampere, kelvin, mole and candela.
- Kilogram : The kilogram is the basic unit of mass in the International System of Units (SI, metric system).
- Kilogram-force : A unit of force which will accelerate 1 kilogram of mass to 9.80665 m/s2, the standard average acceleration due to gravity on Earth's surface (referred to as gn).
- Pound (mass) : A measurement unit of mass used in the United States customary, Imperial, and other systems of measurement.
- Pound-force : A measurement unit of force which will accelerate 1 pound of mass to 9.80665 m/s2 (≈ 32.17405 ft/s2), the standard average acceleration due to gravity on Earth's surface (referred to as gn).
- Tonne : A measurement of mass equal to 1000 kg, or almost exactly the mass of one cubic metre of pure water at 3.98 °C.
- U.S. customary units : The units of measurement that are currently used in the United States.