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प्रश्न
What is the Young’s modulus for a perfect rigid body ?
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उत्तर
Young's modulus `(Y) = F/A xx l/(Δl)`
For a perfectly rigid body, change in length `Δl` = 0
∴ `Y = F/A = l/0 = ∞`
Therefore, Young's modulus for a perfectly rigid body is infinite (∞).
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