the circle by joining points and with a straight line . Draw the Mohr Circle. The centre of the circle is the midpoint of the diameter line , which corresponds to the intersection of this line with the axis. Finding principal normal stresses The magnitude of the principal stresses are the abscissas of the points and (Figure 6) where the circle intersects the -axis. The magnitude of the major principal stress is always the greatest absolute value of the abscissa of any of these two points. Likewise, the magnitude of the minor principal stress is always the lowest absolute value of the abscissa of these two points. As expected, the ordinates of these two points are zero, corresponding to the magnitude of the shear stress components on the principal planes. Alternatively, the values of the principal stresses can be found by where the magnitude of the average normal stress is the abscissa of the centre , given by and the length of the radius of the circle (based on the equation of a circle passing through two points), is given by Finding maximum and minimum shear stresses The maximum and minimum shear stresses correspond to the ordinates of the highest and lowest points on the circle, respectively. These points are located at the intersection of the circle with the vertical line passing through the center of the circle, . Thus, the magnitude of the maximum and minimum shear stresses are equal to the value of the circle's radius Finding stress components on an arbitrary plane As mentioned before, after the two-dimensional stress analysis has been performed we know the stress components , , and at a material point . These stress components act in two perpendicular planes and passing through as shown in Figure 5 and 6. The Mohr circle is used to find the stress components and , i.e., coordinates of any point on the circle, acting on any other plane passing through making an angle with the plane . For this, two approaches can be used: the double angle, and the Pole or origin of planes. Double angle As shown in Figure 6, to determine the stress components acting on a plane at an angle counterclockwise to the plane on which acts, we travel an angle in the same counterclockwise direction around the circle from the known stress point to point , i.e., an angle between lines and