Question

The mean distance between the atoms of iron is $3\times {10}^{-10}m$ and interatomic force constant for iron is $7N{m}^{-1}$. The Young's modulus of electricity for iron is

• A. $2.33\times {10}^{5}N{m}^{-2}$
• B. $23.3\times {10}^{10}N{m}^{-2}$
• C. $2.33\times {10}^{9}N{m}^{-2}$
• D. $2.33\times {10}^{10}N{m}^{-2}$

Answer 1

The correct option is D $2.33\times {10}^{10}N{m}^{-2}$

Given,

Inter atomic distance, $r=3\times {10}^{-10}m$

Interatomic force constant, $K=7N/m$

$Y=?$

Interatomic force constant, $K=Y\times r$

$Y=\frac{K}{r}$

$Y=\frac{7}{3\times {10}^{-10}}$

$Y=2.33\times {10}^{10}N/m^2$

The young's modulus of elasticity of the iron is $2.33\times {10}^{10}N/m^2$.

The correct option is D.