Mohr's circle (subjected to direct stresses in two mutually perpendicular faces and it is accompanied by a shear stress)

Best and easy way to understand and draw the Mohr’s circle 

 Mohr’s circle for stress on an oblique section of a body subjected to direct stresses in two mutually perpendicular faces and it is accompanied by a shear stress




Detailed step by step procedure to draw the mohr's circle for a body subjected to direct stresses in two mutually perpendicular faces (When both stresses are of tensile nature)

Things to remember before drawing mohr's circle 
๐Ÿ‘‰tensile stress is taken as positive and compressive stress is taken as negative.
๐Ÿ‘‰a pair of shear stress on // planes forming a clockwise couple is positive and a pair of shear stress on // planes forming a counter-clockwise couple is negative.
๐Ÿ‘‰ you can use appropriate scale 
for eg. 
ฯƒx (Megapascal) =ฯƒx (centimeter) 
1 MPa=1cm

Step 1. Draw a straight line length OB length equals to ฯƒx.






Step 2. Mark a point A on line OB and Length of OA is equal to ฯƒy .




Step 3. Draw a Perpendicular line AE and BF, length of AE and BF is equal to shear stress ฯ„.



Step 4. Join EF 



Step 5.  Mark a point C at mid point of EF 


Step 6. Draw a circle passing through points E and F 








Step 7. Locate an inclined plane in this circle by marking a radial line CJ at double the angle at which the required plane is inclined with a given plane.







Step 8. Draw JR perpendicular from J to x-axis. 




Now the mohr's circle is completed 


Now we have to find the result value 

1. Normal stress 
measure the length OR(will give the value of normal stress at an inclined plane)

2. Tangential Stress
measure the value JR (will give the value of shear stress at an incline plane)




3. OH will give the maximum Normal stress 
on this plane Tangential Stress will zero so, OH plane will be known as Principal Plane
Angle between CF and CH will give you the position of principal plane



4. CI will give the maximum Tangential Stress














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