The
resultant stress on an inclined plane which is inclined at an angle `theta`
to the normal cross-section of a body which is subjected to a direct
tensile stress (`sigma`) in one plane, is
In leaf springs, the maximum bending stress developed in the plates is (where W = Load acting on the spring, l = Span of the spring, n = Number of plates, b = Width of plates, and t = Thickness of plates)