Convert Fortnights to Shakes
Convert Fortnights (fn) to Shakes (sh) instantly and accurately.
Conversion Formula
sh = fn × 120960000000000
About Fortnights
A fortnight = exactly 14 days = 2 weeks = 1,209,600 s. From Old English 'feowertiene niht' (fourteen nights), reflecting the Germanic custom of counting nights. Common in British, Irish, Australian, and NZ English for pay periods, rental cycles, and parliamentary recesses. The Moon's phase advances ~half a synodic month (≤14.77 days) per fortnight; spring and neap tides also cycle fortnightly. 1 fortnight = 14 d = 1,209,600 s.
About Shakes
A shake = exactly 10 ns (10⁻⁸ s) - the informal unit for fission prompt-neutron generation time, coined at Los Alamos during the Manhattan Project (1943-1945). A prompt-neutron generation in a supercritical core takes ~1-10 shakes; a full explosive chain reaction unfolds over ~50-100 shakes. The name alludes to 'two shakes of a lamb's tail'. Still used in reactor physics and weapons-design calculations. 1 shake = 10 ns.
Quick Reference Table
| Fortnights (fn) | Shakes (sh) |
|---|---|
| 1 fn | 1.21 × 1014 sh |
| 2 fn | 2.419 × 1014 sh |
| 5 fn | 6.048 × 1014 sh |
| 10 fn | 1.21 × 1015 sh |
| 25 fn | 3.024 × 1015 sh |
| 50 fn | 6.048 × 1015 sh |
| 100 fn | 1.21 × 1016 sh |