Convert Seconds to Shakes
Convert Seconds (s) to Shakes (sh) instantly and accurately.
Conversion Formula
sh = s × 100000000
About Seconds
The second (s) is the SI base unit of time, defined since 1967 as exactly 9,192,631,770 periods of the caesium-133 ground-state hyperfine transition at 0 K. Caesium fountain clocks realise this to ~10⁻¹⁶ (1 s lost per ~300 million years); optical lattice clocks (Sr, Yb) reach ~10⁻¹⁸. The second links to the metre via the defined speed of light c = 299,792,458 m/s exactly. 1 s = 1,000 ms = 1/60 min.
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
| Seconds (s) | Shakes (sh) |
|---|---|
| 1 s | 100000000 sh |
| 2 s | 200000000 sh |
| 5 s | 500000000 sh |
| 10 s | 1000000000 sh |
| 25 s | 2.5 × 109 sh |
| 50 s | 5 × 109 sh |
| 100 s | 1 × 1010 sh |