Search results
Results from the WOW.Com Content Network
Heat capacity per unit mass J/(K⋅kg) L 2 T −2 Θ −1: intensive Specific volume: v: Volume per unit mass (reciprocal of density) m 3 ⋅kg −1: L 3 M −1: intensive Spin: S: Quantum-mechanically defined angular momentum of a particle kg⋅m 2 ⋅s −1: L 2 M T −1: Strain: ε: Extension per unit length unitless 1: Stress: σ: Force per ...
The shed is a unit of area used in nuclear physics equal to 10 −24 barns (100 rm 2 = 10 −52 m 2). The outhouse is a unit of area used in nuclear physics equal to 10 −6 barns (100 am 2 = 10 −34 m 2). The barn (b) is a unit of area used in nuclear physics equal to one hundred femtometres squared (100 fm 2 = 10 −28 m 2).
Units for other physical quantities are derived from this set as needed. In English Engineering Units, the pound-mass and the pound-force are distinct base units, and Newton's Second Law of Motion takes the form = where is the acceleration in ft/s 2 and g c = 32.174 lb·ft/(lbf·s 2).
In physics, natural unit systems are measurement systems for which selected physical constants have been set to 1 through nondimensionalization of physical units.For example, the speed of light c may be set to 1, and it may then be omitted, equating mass and energy directly E = m rather than using c as a conversion factor in the typical mass–energy equivalence equation E = mc 2.
[1] An SI derived unit is a named combination of base units such as hertz (cycles per second), newton (kg⋅m/s 2), and tesla (1 kg⋅s −2 ⋅A −1) and in the case of Celsius a shifted scale from Kelvin. Certain units have been officially accepted for use with the SI.
Ampèremetre (Ammeter) A physical quantity (or simply quantity) [1] [a] is a property of a material or system that can be quantified by measurement.A physical quantity can be expressed as a value, which is the algebraic multiplication of a numerical value and a unit of measurement.
"The kelvin, symbol K, is the SI unit of thermodynamic temperature. It is defined by taking the fixed numerical value of the Boltzmann constant k to be 1.380 649 × 10 −23 when expressed in the unit J K −1, which is equal to kg m 2 s −2 K −1, where the kilogram, metre and second are defined in terms of h, c and ∆ν Cs." [1]
SI base units [1]: 136 Unit name Unit symbol Dimension symbol Quantity name Typical symbols Definition second: s time: The duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom. metre: m