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##### Question: 1

Q no: 5 (A) Derive the formula of Young Modulus.?<div><br></div>

##### Answer: 1

1-24Young's Modulus:

The ratio of stress and strain is a constant within the elastic limit , this constant is called the young's Modulus.

Mathematical Form:

Consider a long bar of length Land cross- sectional area A let an external force F is equal to weight stretches it such that the stretched length becomes L.

_{o}Mathematically.

Young's Modulus = Y = Stress/Tensile strain

Let ▲L =L-L

_{o}Since-

Stress = Force/Area =F/A

And

Tensile strain = L-L

_{o}/L_{o}= ▲L/L_{o}As

Young's modulus = Y = Stress/Tensile strain

=F/A x L

_{o}/▲L = F x L

_{o}/A x▲L