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According to Griffith theory, which of the following are true for the fracture stress in a brittle material?
P. Increases with increasing surface energy
Q. Decreases with increasing elastic modulus
R. Decreases with increasing length of pre-existing crack
S. Decreases with increasing number of pre-existing cracks of same size

According to Griffith theory, which of the following are true for the fracture stress in a brittle material?
P. Increases with increasing surface energy
Q. Decreases with increasing elastic modulus
R. Decreases with increasing length of pre-existing crack
S. Decreases with increasing number of pre-existing cracks of same size Correct Answer Q, R, S

Related Questions

A brittle material is mechanically tested in medium P in which it has surface energy γs = 0.9 J m-2. This material has a fracture strength of 300 MPa for a given flaw size. The same solid containing the same flaws is then tested in medium Q in which γs = 0.1 J m-2. The fracture strength (in MPa) in medium Q based on Griffith's theory is
From an alloy, two specimens are machined and tested separately under tension and compression. The engineering stress-strain curves as well as the true stress-true strain curves for tension and compression are plotted in the same diagram. Identify the correct statements:
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