15: Force
- Page ID
- 91879
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Intuitively, a force is a push or a pull. In SI units, force is measured in units of newtons (N), named for the English physicist Sir Isaac Newton. In terms of base units,
\[1 \mathrm{~N}=1 \frac{\mathrm{kg} \; \mathrm{m}}{\mathrm{s}^{2}} \]
In CGS units, force is measured in dynes (dyn):
\[1 \text { dyne }=1 \frac{\mathrm{g} \; \mathrm{cm}}{\mathrm{s}^{2}} .\]
In the British engineering system, force is measured in pounds (lb). This is sometimes called pounds-force (lbf) when it's important to clearly distinguish it from pounds-mass ( \(\mathrm{lbm}\) ).
\[1 \mathrm{lbf}=1 \frac{\text { slug } \;\mathrm{ft}}{\mathrm{s}^{2}}\]