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The statement of Griffith theory of brittle fracture says that “A crack will propagate when the decrease in elastic strain energy is at least equal to the energy required to create the new surface”.

The statement of Griffith theory of brittle fracture says that “A crack will propagate when the decrease in elastic strain energy is at least equal to the energy required to create the new surface”. Correct Answer True

The idea behind the Griffith theory is that every material contains micro-cracks and in the local region of crack tip, the stress concentration causes the stress value high enough to cross the theoretical fracture stress of the material.

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