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a.u. of length
Symbol:  a.u., a0, b 
Category:  Length 
SI Equivalent:  5.29177×10-11 m
Dimension:  L 
System:  a.u. 
 
Notes
Also called the 1st Bohr radius, this fundamental physical constant is a base unit of the a.u. system.
Convert     a.u., a0, b  
1 a.u., a0, b =
Length
  Symbol Unit Name
0.529177  Å  angstrom 
1.81918×10-7  arcmin  arcmin 
3.53733×10-22  AU, UA  astronomical unit 
5.29177×107  am  attometer 
6.25013×10-9    barleycorn (UK) 
1  a0, b  bohr (first Bohr radius) 
1.44679×10-12    bolt (US cloth) 
2.50005×10-8  line (UK)  button (UK) 
8.3335×10-8  line (US)  button (US) 
2.85733×10-13    cable length (int.) 
2.8555×10-13    cable length (UK) 
2.41131×10-13    cable length (US) 
2.08337×10-7  caliber, cin  caliber (centiinch) 
5.29177×10-9  cm  centimeter 
1.73615×10-12  ch  chain (engineer's) 
2.63052×10-12  ch  chain (Gunter's) 
1.73615×10-12  ch  chain (Ramsden's) 
2.63052×10-12  ch  chain (surveyor's) 
1.15743×10-10    cubit (UK) 
5.29177×10-12  dam  decameter 
5.29177×10-10  dm  decimeter 
1.87789×104  re  electron classical radius 
4.62972×10-11    ell 
1.25472×10-8    ems (pica) 
5.29177×10-29  Em  exameter 
2.89358×10-11  fath  fathom 
5.29177×104  fm  femtometer 
5.29177×104  F, f  fermi 
1  a0, b, a.u.  first Bohr radius 
1.73615×10-10  ft  foot 
1.58753×10-7  fr  French 
2.63052×10-13  fur  furlong (UK) 
2.63052×10-13  fur  furlong (US) 
5.29177×10-20  Gm  gigameter 
5.20844×10-10  hd  hand (UK) 
5.29177×10-13  hm  hectometer 
5.59353×10-36    hubble 
2.08338×10-9  in  inch 
5.29177×10-14  km  kilometer 
1.71495×10-30  kpc  kiloparsec 
1.09629×10-14    league (Canadian) 
9.52443×10-15  leag. (int. naut.)  league (int. naut.) 
1.09605×10-14  leag. (stat.)  league (statute, land) 
9.51834×10-15  leag. (UK, naut.)  league (UK, naut.) 
9.51834×10-15  leag. (US, naut.)  league (US, naut.) 
2.04299×10-24    light-day 
4.90318×10-23    light-hour 
2.94191×10-21    light-minute 
1.76515×10-19    light-second 
5.59353×10-27  ly  light-year 
2.50005×10-8  line (UK)  line (UK) 
8.3335×10-8  line (US)  line (US) 
1.73615×10-10    link (engineer's) 
2.63052×10-10    link (Gunter's) 
1.73615×10-10    link (Ramsden's) 
2.63052×10-10    link (surveyor's) 
5.29177×10-17  Mm  megameter 
5.29177×10-11  m  meter 
2.08338×10-3  µin  microinch 
5.29177×10-5  µm  micron 
2.08337×10-6  mil, thou  mil (thou) 
7.13024×10-15  mile (geogr.)  mile (geographical) 
3.28815×10-14  mi (int.)  mile (international) 
2.85733×10-14  mi (naut., int.)  mile (nautical, international) 
2.85222×10-14  mi (naut., teleg.)  mile (nautical, telegraph) 
2.8555×10-14  mi (naut., UK, US)  mile (nautical, UK, US) 
3.28816×10-14  mi (stat.)  mile (statute, land) 
3.28815×10-14  mi (survey, US)  mile (survey, US) 
5.29177×10-8  mm  millimeter 
5.29177×10-2  mµ, nm  millimicron 
2.31486×10-10    nail (UK) 
5.29177×10-2  nm  nanometer 
2.85733×10-14  mi (int. naut.)  nautical mile (international) 
2.8555×10-14  mi (UK, US, naut.)  nautical mile (UK, US) 
6.94458×10-11    pace (UK) 
6.94458×10-10    palm (UK) 
1.71495×10-27  pc  parsec 
1.05221×10-11  rd  perch (rod, pole) 
5.29177×10-26  Pm  petameter 
1.25471×10-8    pica 
52.9177  pm  picometer 
1.50566×10-7    point (US printer's) 
1.05221×10-11  rd  pole (rod, perch) 
5.29177×10-18    quadrant 
1.05221×10-11  rd  rod (perch, pole) 
8.68073×10-12    rope (UK) 
2.31486×10-10    span 
5.29177×10-23  Tm  terameter 
2.08337×10-6  thou, mil  thou (mil) 
529.067  UX, X  X-unit 
5.78715×10-11  yd  yard 
5.29177×1013  ym  yoctometer 
5.29177×10-35  Ym  yottameter 
5.29177×1010  zm  zeptometer 
5.29177×10-32  Zm  zettameter 
Glossary
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