What is the difference between stiffness and Young Modulus and how can you calculate the stiffness?
Stiffness is the rigidity of an object — the extent to which it resists deformations in response to an applied force
Stiffness k = Force applied/displacement produced by the force
the young modulus or modulus of elasticity can be related to stiffness though the two properties are different in the sense that elasticity is an intensive propert wheras stiffness is extensive one.
for details one can see wikipedia
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