| fermtometer | 1 fm | 2 fm | 3 fm | 4 fm | 5 fm | 6 fm | 7 fm | 8 fm | 9 fm | 10 fm | 11 fm | 12 fm | 13 fm | 14 fm | 15 fm | 16 fm | 17 fm | 18 fm | 19 fm | 20 fm | 21 fm | 22 fm | 23 fm | 24 fm | 25 fm | 26 fm | 27 fm | 28 fm | 29 fm | 30 fm | 31 fm | 32 fm | 33 fm | 34 fm | 35 fm | 36 fm | 37 fm | 38 fm | 39 fm | 40 fm | 41 fm | 42 fm | 43 fm | 44 fm | 45 fm | 46 fm | 47 fm | 48 fm | 49 fm | 50 fm | 51 fm | 52 fm | 53 fm | 54 fm | 55 fm | 56 fm | 57 fm | 58 fm | 59 fm | 60 fm | 61 fm | 62 fm | 63 fm | 64 fm | 65 fm | 66 fm | 67 fm | 68 fm | 69 fm | 70 fm | 71 fm | 72 fm | 73 fm | 74 fm | 75 fm | 76 fm | 77 fm | 78 fm | 79 fm | 80 fm | 81 fm | 82 fm | 83 fm | 84 fm | 85 fm | 86 fm | 87 fm | 88 fm | 89 fm | 90 fm | 91 fm | 92 fm | 93 fm | 94 fm | 95 fm | 96 fm | 97 fm | 98 fm | 99 fm | 100 fm |
| light-hour | 9.2656693110598 × 10-28 light-hour | 1.853133862212 × 10-27 light-hour | 2.7797007933179 × 10-27 light-hour | 3.7062677244239 × 10-27 light-hour | 4.6328346555299 × 10-27 light-hour | 5.5594015866359 × 10-27 light-hour | 6.4859685177418 × 10-27 light-hour | 7.4125354488478 × 10-27 light-hour | 8.3391023799538 × 10-27 light-hour | 9.2656693110598 × 10-27 light-hour | 1.0192236242166 × 10-26 light-hour | 1.1118803173272 × 10-26 light-hour | 1.2045370104378 × 10-26 light-hour | 1.2971937035484 × 10-26 light-hour | 1.389850396659 × 10-26 light-hour | 1.4825070897696 × 10-26 light-hour | 1.5751637828802 × 10-26 light-hour | 1.6678204759908 × 10-26 light-hour | 1.7604771691014 × 10-26 light-hour | 1.853133862212 × 10-26 light-hour | 1.9457905553226 × 10-26 light-hour | 2.0384472484332 × 10-26 light-hour | 2.1311039415437 × 10-26 light-hour | 2.2237606346543 × 10-26 light-hour | 2.3164173277649 × 10-26 light-hour | 2.4090740208755 × 10-26 light-hour | 2.5017307139861 × 10-26 light-hour | 2.5943874070967 × 10-26 light-hour | 2.6870441002073 × 10-26 light-hour | 2.7797007933179 × 10-26 light-hour | 2.8723574864285 × 10-26 light-hour | 2.9650141795391 × 10-26 light-hour | 3.0576708726497 × 10-26 light-hour | 3.1503275657603 × 10-26 light-hour | 3.2429842588709 × 10-26 light-hour | 3.3356409519815 × 10-26 light-hour | 3.4282976450921 × 10-26 light-hour | 3.5209543382027 × 10-26 light-hour | 3.6136110313133 × 10-26 light-hour | 3.7062677244239 × 10-26 light-hour | 3.7989244175345 × 10-26 light-hour | 3.8915811106451 × 10-26 light-hour | 3.9842378037557 × 10-26 light-hour | 4.0768944968663 × 10-26 light-hour | 4.1695511899769 × 10-26 light-hour | 4.2622078830875 × 10-26 light-hour | 4.3548645761981 × 10-26 light-hour | 4.4475212693087 × 10-26 light-hour | 4.5401779624193 × 10-26 light-hour | 4.6328346555299 × 10-26 light-hour | 4.7254913486405 × 10-26 light-hour | 4.8181480417511 × 10-26 light-hour | 4.9108047348617 × 10-26 light-hour | 5.0034614279723 × 10-26 light-hour | 5.0961181210829 × 10-26 light-hour | 5.1887748141935 × 10-26 light-hour | 5.2814315073041 × 10-26 light-hour | 5.3740882004147 × 10-26 light-hour | 5.4667448935253 × 10-26 light-hour | 5.5594015866359 × 10-26 light-hour | 5.6520582797465 × 10-26 light-hour | 5.7447149728571 × 10-26 light-hour | 5.8373716659677 × 10-26 light-hour | 5.9300283590783 × 10-26 light-hour | 6.0226850521889 × 10-26 light-hour | 6.1153417452995 × 10-26 light-hour | 6.2079984384101 × 10-26 light-hour | 6.3006551315206 × 10-26 light-hour | 6.3933118246312 × 10-26 light-hour | 6.4859685177418 × 10-26 light-hour | 6.5786252108524 × 10-26 light-hour | 6.671281903963 × 10-26 light-hour | 6.7639385970736 × 10-26 light-hour | 6.8565952901842 × 10-26 light-hour | 6.9492519832948 × 10-26 light-hour | 7.0419086764054 × 10-26 light-hour | 7.134565369516 × 10-26 light-hour | 7.2272220626266 × 10-26 light-hour | 7.3198787557372 × 10-26 light-hour | 7.4125354488478 × 10-26 light-hour | 7.5051921419584 × 10-26 light-hour | 7.597848835069 × 10-26 light-hour | 7.6905055281796 × 10-26 light-hour | 7.7831622212902 × 10-26 light-hour | 7.8758189144008 × 10-26 light-hour | 7.9684756075114 × 10-26 light-hour | 8.061132300622 × 10-26 light-hour | 8.1537889937326 × 10-26 light-hour | 8.2464456868432 × 10-26 light-hour | 8.3391023799538 × 10-26 light-hour | 8.4317590730644 × 10-26 light-hour | 8.524415766175 × 10-26 light-hour | 8.6170724592856 × 10-26 light-hour | 8.7097291523962 × 10-26 light-hour | 8.8023858455068 × 10-26 light-hour | 8.8950425386174 × 10-26 light-hour | 8.987699231728 × 10-26 light-hour | 9.0803559248386 × 10-26 light-hour | 9.1730126179492 × 10-26 light-hour | 9.2656693110598 × 10-26 light-hour |
The femtometre (American spelling femtometer, symbol fm derived from the Danish and Norwegian word femten, "fifteen"+Ancient Greek: μέτρον, metrοn, "unit of measurement") is an SI unit of length equal to 10−15 metres, which means a quadrillionth of one. This distance can also be called a fermi and was so named in honour of physicist Enrico Fermi, as it is a typical length-scale of nuclear physics.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| fermtometer | fm | 1000 attometres = 1 femtometre = 1 fermi = 0.001 picometre = 1×10−15 metres 1000000 femtometres = 10 ångström = 1 nanometre. | ≡ 1×10-15 m | Metric system SI |
| fermtometers | light-hours | fermtometers | light-hours |
|---|---|---|---|
| 1 | ≡ 9.2656693110598E-28 | 4 | ≡ 3.7062677244239E-27 |
| 1.5 | ≡ 1.389850396659E-27 | 4.5 | ≡ 4.1695511899769E-27 |
| 2 | ≡ 1.853133862212E-27 | 5 | ≡ 4.6328346555299E-27 |
| 2.5 | ≡ 2.3164173277649E-27 | 5.5 | ≡ 5.0961181210829E-27 |
| 3 | ≡ 2.7797007933179E-27 | 6 | ≡ 5.5594015866359E-27 |
The light-hour is a unit of length useful in astronomy, telecommunications and relativistic physics. It is defined as the distance that light travels in free space in onehour, and is equal to exactly 1.0792528488×1012 metres.
| Name of unit | Symbol | Definition | Relation to SI units | Unit System |
|---|---|---|---|---|
| light-hour | ≡ 60 light-minutes | ≡ 1.0792528488×1012 m | Science - Astronomy (Length) |
| light-hours | fermtometers | light-hours | fermtometers |
|---|---|---|---|
| 1 | ≡ 1.0792528488E+27 | 4 | ≡ 4.3170113952E+27 |
| 1.5 | ≡ 1.6188792732E+27 | 4.5 | ≡ 4.8566378196E+27 |
| 2 | ≡ 2.1585056976E+27 | 5 | ≡ 5.396264244E+27 |
| 2.5 | ≡ 2.698132122E+27 | 5.5 | ≡ 5.9358906684E+27 |
| 3 | ≡ 3.2377585464E+27 | 6 | ≡ 6.4755170928E+27 |
| fermtometers | light-hours |
|---|---|
| 1 | ≡ 9.2656693110598 × 10-28 |
| 1.0792528488 × 1027 | ≡ 1 |
| Symbol | Definition |
|---|---|
| ≡ | exactly equal |
| ≈ | approximately equal to |
| = | equal to |
| digits | indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …) |