MCQ
The value of Young's modulus for a perfectly rigid body is ...........
  • A
    $1$
  • B
    Less than $1$
  • C
    Zero
  • Infinite

Answer

Correct option: D.
Infinite
d
(d)

For perfectly rigid body the condition is that there should not be any elognation $(\Delta L=0)$ for any value of force

So from the formulae we know $\frac{F L}{A \cdot \Delta L}=Y$

If we put $\Delta L=0$

We get $Y$ as $\infty$

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