4. The bar has cross-sectional area A and modulus of elasticity E. If an axial force F directed toward the right is applied at C
1 answer:
Answer:
a) ΔL/L = F / (E A), b) = L (1 + L F /(EA) )
Explanation:
Let's write the formula for Young's module
E = P / (ΔL / L)
Let's rewrite the formula, to have the pressure alone
P = E ΔL / L
The pressure is defined as
P = F / A
Let's replace
F / A = E ΔL / L
F = E A ΔL / L
ΔL / L = F / (E A)
b) To calculate the elongation we must have the variation of the length, so the length of the bar must be a fact. Let's clear
ΔL = L [F / EA]
-L = L (F / EA)
= L + L (F / EA)
= L (1 + L (F / EA))
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