ConstantID

Electromagnetic constants

The elementary charge, magnetons, the quantum standards of voltage and resistance, and the 1990 conventional electrical units.

Electromagnetic μB Bohr magneton 9.274 010 0657(29) × 10−24 J T−1 Electromagnetic exact e Elementary charge 1.602 176 634 × 10−19 C Electromagnetic exact KJ Josephson constant 483 597.8484… × 109 Hz V−1 Electromagnetic exact RK von Klitzing constant 25 812.807 45… Ω

All 26 values

SymbolQuantityValue (uncertainty)UnitRel. unc.
μB Bohr magneton 9.274 010 0657(29) × 10−24 J T−1 3.1 × 10−10
μB Bohr magneton in eV/T 5.788 381 7982(18) × 10−5 eV T−1 3.1 × 10−10
μB/h Bohr magneton in Hz/T 1.399 624 491 71(44) × 1010 Hz T−1 3.1 × 10−10
μB/hc Bohr magneton in inverse meter per tesla 46.686 447 719(15) m−1 T−1 3.2 × 10−10
μB/k Bohr magneton in K/T 0.671 713 814 72(21) K T−1 3.1 × 10−10
G0 Conductance quantum 7.748 091 729… × 10−5 S exact
A90 Conventional value of ampere-90 1.000 000 088 87… A exact
C90 Conventional value of coulomb-90 1.000 000 088 87… C exact
F90 Conventional value of farad-90 0.999 999 982 20… F exact
H90 Conventional value of henry-90 1.000 000 017 79… H exact
KJ-90 Conventional value of Josephson constant 483 597.9 × 109 Hz V−1 exact
Ω90 Conventional value of ohm-90 1.000 000 017 79… Ω exact
V90 Conventional value of volt-90 1.000 000 106 66… V exact
RK-90 Conventional value of von Klitzing constant 25 812.807 Ω exact
W90 Conventional value of watt-90 1.000 000 195 53… W exact
e Elementary charge 1.602 176 634 × 10−19 C exact
e/ℏ Elementary charge over h-bar 1.519 267 447… × 1015 A J−1 exact
G0−1 Inverse of conductance quantum 12 906.403 72… Ω exact
KJ Josephson constant 483 597.8484… × 109 Hz V−1 exact
Φ0 Magnetic flux quantum 2.067 833 848… × 10−15 Wb exact
μN Nuclear magneton 5.050 783 7393(16) × 10−27 J T−1 3.2 × 10−10
μN Nuclear magneton in eV/T 3.152 451 254 17(98) × 10−8 eV T−1 3.1 × 10−10
μN/hc Nuclear magneton in inverse meter per tesla 2.542 623 410 09(79) × 10−2 m−1 T−1 3.1 × 10−10
μN/k Nuclear magneton in K/T 3.658 267 7706(11) × 10−4 K T−1 3.0 × 10−10
μN/h Nuclear magneton in MHz/T 7.622 593 2188(24) MHz T−1 3.1 × 10−10
RK Von Klitzing constant 25 812.807 45… Ω exact