Can someone answer #20 and #21 20 Principal stresses at a point in an element ar

Question

Can someone answer #20 and #21

20 Principal stresses at a point in an element are Principal the (a) minimum and maximum shear stresses at that (b) the minimum and maximum normal stresses at that point (c) average and maximum normal stresses at that point (d) the minimum and maximum normal and shear stresses at that point 21. For plane stress condition, 50 Pa and or 60 Pa. If the cubic element is rotated by angle 30°, counterclockwise, and a 40 Pa in the new plane. Calculate the normal stress in the y direction, or (a) 52 Pa (b) 30 Pa (c) 70 Pa d) 35 Pa

Explanation / Answer

20) Principal Stresses at a point in an element are the minimum and maximum normal sresses at that point. So answer (b) is right.

21) From stress Invariant we know, (Stress)x+(Stress)y=(Stress)'x+(Stress)'y

or, 50+60=40+(Stress)'y

or, (Stress)'y=50+60-40=70

So, answer (c) is right.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---