 Welcome back mechanically, did you know that direct and bending stresses are the two types of stresses which determine the shape in which a given rod undergoes buckling? This makes us wonder, what are direct and bending stresses? Before we jump in check out the previous part of the series to learn about what flinched beams are. Now stresses developed due to axial loading that is along the axis is direct stress. It is denoted by sigma D and is given by applied load upon cross sectional area. The stress developed due to eccentric loading that is away from the axis is bending stress. It is denoted by sigma B. If the loading is eccentric, the total maximum stress will be the summation of direct stress and bending stress. It is denoted by sigma D and is the sum of sigma B and sigma D. Direct load may be of any type, concentrated, moment couple, distributed etc. A region around the centre of gravity of the cross section of a rod, the core of a cross section has a property that a longitudinal force applied to any point of the core causes a stress of one sign in this section. The shape and size of the core of a cross section are specified by the shape and size of the rod. The determination of the core of a cross section is especially important in the designing of rods made of materials that have different tensile and compressive strengths. Hence, we first saw what direct and bending stresses are and then went on to find out what core of a cross section is. So like, subscribe and comment with your feedback to help us make better videos. Thanks for watching. Also, thanks a lot for those constructive comments. You help the channel grow. So, here are the top mechanical EIs of our last videos. In the next episode of Mechanical EI, find out how a shear stress distributed.