Convert Femtonewtons to Long Ton-Force
Convert Femtonewtons (fN) to Long Ton-Force (tf (UK)) instantly and accurately.
Conversion Formula
tf (UK) = fN × 1.003611353e-19
About Femtonewtons
A femtonewton (fN) is 10⁻¹⁵ N - the force scale of single-molecule biology. RNA polymerase exerts a stall force of ~14-25 fN while transiting DNA at 10-50 bp/s. Myosin V motor proteins step 37 nm with ~1-3 fN per head. The viscous drag on a 100 nm nanoparticle moving at 1 µm/s through cytoplasm is ~0.2-0.5 fN. Optical tweezers with back-focal-plane detection resolve sub-femtonewton forces, enabling measurement of single-enzyme output. AFM receptor-ligand unbinding (e.g., biotin-streptavidin) gives adhesion forces of 100-300 fN. 1 fN = 10⁻¹⁵ N.
About Long Ton-Force
One long ton-force is the gravitational force on an imperial long ton (2,240 lb = 20 × 112 lb hundredweight) - approximately 9,964 N. The long ton was the traditional British ton; long ton-force appears in Royal Navy vessel displacement records, British Admiralty anchor chain standards, pre-metrication UK bridge live load codes, and Australian/South African mining bolt pull-out specifications. It sits between short ton-force (8,896 N) and metric tonne-force (9,807 N) - about 12% heavier than a short ton-force. 1 long tf = 2,240 lbf = 9,964.02 N.
Quick Reference Table
| Femtonewtons (fN) | Long Ton-Force (tf (UK)) |
|---|---|
| 1 fN | 1.004 × 10-19 tf (UK) |
| 2 fN | 2.007 × 10-19 tf (UK) |
| 5 fN | 5.018 × 10-19 tf (UK) |
| 10 fN | 1.004 × 10-18 tf (UK) |
| 25 fN | 2.509 × 10-18 tf (UK) |
| 50 fN | 5.018 × 10-18 tf (UK) |
| 100 fN | 1.004 × 10-17 tf (UK) |