Curvature $k$
How a line bends or curves. One-dimensional only. Upwards-curving (“happy smile”) gives a positive curvature; downwards-curving (“sad smile”) a negative curvature.
$$k=\frac 1r$$
$r$ is radius of the imagined circle that the curve is a part of.
- Scalar property
- Symbol: $k$
- SI-unit: Inverse metres $\mathrm{m^{-1}}$
