The length of a rod is 20 cm and area of cross-section 2 ${\mathrm{cm}}^2$. The Young's modulus of the material of wire is $1.4\times {10}^{11} \mathrm{N}/{\mathrm{m}}^2$. If the rod is compressed by 5 kg-wt along its length, then increase in the energy of the rod in joules will be

• A

  $8.57\times {10}^{-6}$

• B

  $22.5\times {10}^{-4}$

• C

  $9.8\times {10}^{-5}$

• D

  $45.0\times {10}^{-5}$