Question

Choose the correct option.
Statement 1: Hooke's law is obeyed only for small values of strain.
Statement 2: The permanent deformation beyond elastic limit is called plasticity.

• A. Statement 1 is correct but statement 2 is wrong
• B. Statement 1 is wrong but statement 2 is correct
• C. Both statement 1 and statement 2 are correct
• D. Both statement 1 and statement 2 are wrong

Answer 1

The correct option is C Both statement 1 and statement 2 are correct

Hooke's law is defined within the proportional limit. So, the object returns to its original shape when the force is removed i.e the deformation is elastic for small deformations.
Beyond elastic limit, any deformation caused is permanent (plastic) and it cannot be restored once the force is removed. So, it is region of plasticity.
$\therefore$ Both statement 1 and statement 2 are correct