A curve is, an object similar to a line but that it is not straight. Any curve which does not cross itself is called as a Simple curve. The sharpness of simple curve is also determined by radius R. Here is the Simple Curve Formula which will guide you to calculate the degree of the curve in approximate. Also, this Simple circular curve formula provides you the formulas to calculate the length of curve, length of tangent, external distance, length of long chord and middle ordinate.