Search results
Results From The WOW.Com Content Network
The base unit in the International System of Units (SI) is the meter, defined as "the length of the path travelled by light in vacuum during a time interval of 1 ⁄ 299792458 seconds." [ 9 ] It is approximately equal to 1.0936 yd .
The Planck time is the time that light takes to travel one Planck length. The TU (for time unit) is a unit of time defined as 1024 μs for use in engineering. The svedberg is a time unit used for sedimentation rates (usually of proteins). It is defined as 10 −13 seconds (100 fs).
[1]: 137 For example, the metre, kilometre, centimetre, nanometre, etc. are all SI units of length, though only the metre is a coherent SI unit. The complete set of SI units consists of both the coherent set and the multiples and sub-multiples of coherent units formed by using the SI prefixes. [1]: 138
10 −14 qs: The length of one Planck time (t P = / ≈ 5.39 × 10 −44 s) [3] is the briefest physically meaningful span of time. It is the unit of time in the natural units system known as Planck units. 10 −30: quectosecond: qs Quectosecond, (quecto-+ second), is one nonillionth of a second 10 −27: rontosecond: rs
The word "minute" comes from the Latin pars minuta prima, meaning "first small part", and "second" from pars minuta secunda or "second small part". Angular measure also uses sexagesimal units; there, it is the degree that is subdivided into minutes and seconds, while in time, it is the hour.
The atomic units have been chosen to use several constants relating to the electron: the electron mass, the elementary charge, the Coulomb constant and the reduced Planck constant. The unit of energy in this system is the total energy of the electron in the Bohr atom and called the Hartree energy. The unit of length is the Bohr radius.
Length; Name of unit Symbol Definition Relation to SI units ångström: Å ≡ 1 × 10 −10 m: ≡ 0.1 nm astronomical unit: au ≡ 149 597 870 700 m ≈ Distance from Earth to Sun ≡ 149 597 870 700 m [1] attometre: am ≡ 1 × 10 −18 m: ≡ 1 × 10 −18 m: barleycorn (H) = 1 ⁄ 3 in (see note above about rounding) = 8.4 6 × 10 −3 m ...
The beard-second is a unit of length inspired by the light-year, but applicable to extremely short distances such as those in integrated circuits. It is the length an average beard grows in one second. Kemp Bennett Kolb defines the distance as exactly 100 angstroms (10 nanometres), [8] as does Nordling and Österman's Physics Handbook. [9]