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I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. At a point subjected to plane stress on the surface of a compressed air cylinder, the stresses are σx = –18 ksi, σy = 22 ksi, and τxy = –8 ksi. Determine normal stress σt at the point for a counterclockwise coordinate rotation of 38°.

Create 5 variations of the following problem but do not show the answers. At a point subjected to plane stress on the surface of a backhoe, the stresses are σx = 40 MPa, σy = 70 MPa, and τxy = –100 MPa. Determine the angle θp corresponding to the orientation of the principal planes at the point.

I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. A silicone rubber [E = 5.20 MPa, G = 1.80 MPa] wristband has an initial length of 99 mm and a width of 13 mm. If the wearer imparts a normal stress of 500 kPa in the length direction while putting it on, what is the corresponding change in width?

I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. At a point subjected to plane stress on the surface of a compressed air cylinder, the stresses are σx = –27 ksi, σy = –19 ksi, and τxy = –26 ksi. Determine shear stress τnt at the point for a clockwise coordinate rotation of 84°.

I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. A silicone rubber [E = 7.50 MPa, G = 2.50 MPa] wristband has an initial length of 104 mm and a width of 9 mm. If the wearer imparts a normal stress of 440 kPa in the length direction while putting it on, what is the corresponding change in width?

I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. A silicone rubber [E = 4.70 MPa, G = 1.60 MPa] wristband has an initial length of 99 mm and a width of 10 mm. If the wearer imparts a normal stress of 410 kPa in the length direction while putting it on, what is the corresponding change in width?

Create 5 variations of the following problem but do not show the answers. At a point subjected to plane stress on the surface of a backhoe, the stresses are σx = 7 ksi, σy = –28 ksi, and τxy = 19 ksi. Determine the angle θp corresponding to the orientation of the principal planes at the point.

I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. At a point in a body subjected to plane strain, the strains are εx = –20 με, εy = 430 με, and γxy = 810 μrad. Determine the diameter D of the corresponding in-plane Mohr’s circle.

I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. At a point in a body subjected to plane strain, the strains are εx = 307 με, εy = 489 με, and γxy = –390 μrad. Determine the center εcenter of the corresponding in-plane Mohr’s circle.

I am a teacher and need help creating exam problems. Please recommend more incorrect answers to the following problem but do not explain your logic. A Mohr’s circle is shown for a point in a physical object that is subjected to plane stress. If 1 grid square = 7 MPa, determine the stress τxy.