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GATE 2017 ME (ME2) – Question 47

Machine Design · Design for static and dynamic loading, failure theories · 2 marks · Multiple choice

Principal stresses are 60, 5 and −40 MPa. Tensile yield strength is 200 MPa. The maximum-shear-stress factor of safety is ______.

  1. 1.67
  2. 2.00
  3. 3.60
  4. 4.00

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Correct answer: (B) 2.00

Explanation

The largest principal-stress difference is60−(−40)=100MPa, so maximum shear is50MPa. At uniaxial yield, allowable maximum shear is200/2=100MPa. Safety factor is100/50=**2, B**. The intermediate principal stress does not control the maximum difference.