How is the degree of curvature defined along the roadway?

The degree of curvature along a roadway is a measure that describes how sharply a road turns, and it is typically calculated based on the radius of the curve. One common standard used in roadway design is that the degree of curvature is defined as the angle subtended by a 100-foot arc of the curve. This means that if a curve has a degree of curvature of, for example, 1 degree, this signifies that if you were to travel along the curve for a distance of 100 feet, you would have turned an angle of 1 degree.

Using 100 feet as the basis for defining the degree of curvature allows designers to consistently measure and compare the sharpness of curves on different roadways. Larger degrees of curvature indicate sharper turns, while smaller degrees denote gentler curves. This standardization helps in the planning and safety assessment of roads, allowing road engineers to ensure that the curvature is suitable for vehicle speeds and safety requirements.

The other choices, while they represent various lengths, do not align with the established standard for defining the degree of curvature in roadway engineering.