id like to think i did this right, but i just want to make sure. i cant do symbols so let d equal sigma.(adsbygoogle = window.adsbygoogle || []).push({});

the stress components are d_xx= 200 MPa, d_xy= 50 MPa, d_yy=-100 MPa. I need to find the max shear stress, and the principal stresses, and then a_s and a_p.

heres what i got:

max shear= 158

principal stresses= 108 and 208

a_s=-35.8 degrees

a_p=9.2 degrees

am i right?; im not sure if i need to do anything different since d_yy is negative? i think i used the right equations but not sure, and what would my units be for the stresses ? MPa?

lastly, it asks "denote them on the stress element" (them meaning the things i just found). theres the generic 2-D square with sigma_yy going up from the top, sigma_xx from the right, and sigma_xy parallel to the square. what am i supposed to do about that?

thanks a ton in advance

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# Shear and principal stress

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