HiI've started a mechanics module and just wanted to know, what is

[jase951]

Hi

I've started a mechanics module and just wanted to know, what is the difference between Young's Modulus ('e') and the E = Stress/Strain?

Thanks!

Jase

 

[Claws]

None :)

 

[jase951]

I had a feeling that was going to be the answer.

One last question about 'E': is this the stiffness of the structure or is this a property of the material stiffness only?

Thanks!

 

[ThalorB]

Depending on the type of structure, you would define stiffness with K = F/x, or an "effective" or "apparent" modulus.

In the case of the modulus, a "black box" would enclose your structure and you would determine the properties of that "box," e.g., the cross-sectional area of the box when calculating force/area = pressure.

 

[jase951]

Thanks for your help. I've got it now.

 

[Dadface]

Strictly speaking E is tensile stress/ tensile strain.There is a shear modulus(shear stress/shear strain) and a bulk modulus(bulk stress/bulk strain).