Is every Elastic Material linear?

Difference between linear elastic and non linear elastic materials, some confusions like
1) Is every Elastic material linear?
2) Where to apply Hooke's Law?
3) What Young's modulus indicate?
4) Is Rubber more elastic than Steel?
5) What is Young's modulus for non linear elastic material?
are discussed in this video.

[@ugurkaradag2955]

Hello I have a question ; Aggregates are generally linearly elastic. Cement paste is also linearly elastic. Concrete is non-linearly elastic. Can you Briefly explain the reason please.

[@rishitaroy5612]

Thank u ,....u clear my doubt of elastic modulus. Sir please can u tell me, is taking average elastic modulus valid for concrete also?

[@DEXTER-dv5de]

Hey could you explain me this. In proportional limit it returns to its original position after force is removed , eg the material returns to its original position at 15cm length and in elastic limit it also returns to its original position . Does that mean elastic limit also returns to its original length at 15cm ?

[@viewdmechanical71]

Elastic limit and proportional limit are almost same, except that the stress-strain curve remains linear upto proportional limit and its non linear from proportional to elastic limit. That means upto proportional limit, the deformation increases proportionately with increase in stress.

[@prasanthn3814]

hi. Could you explain design of machine elements and strength of materials, failure theories?

[@viewdmechanical71]

I will make