# State Hook's law on what factors does the modulus of elasticity of a subtance depend?

### Asked by souravkheto234 | 17th Jun, 2021, 12:13: PM

Expert Answer:

### Hooks law states that for small deformations the stress and strain are proportional to each other.
Thus, stress strain
stress = Y × strain .......................... (1)
where Y is the proportionality constant and is known as modulus of elasticity.

Stress is restoring force per unit area . If F is the force applied and A is the area of cross section of the body,
Magnitude of the stress = F/A ...................(2)

Longitudinal strain is change in the length ΔL to the original length L of the body .
Longitudinal strain = ΔL / L ............................(3)
Using above equations (1), (2) and (3) , we get modulus of elsticity as
Y = ( F / A ) / ( ΔL / L )
From above expression, we know , modulus of elsticity depends on what factors are .

### Answered by Thiyagarajan K | 17th Jun, 2021, 01:01: PM

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