For a solid rod, the Young's modulus of elasticity is $3.2\times {10}^{11} \mathrm{N} {\mathrm{m}}^{-2}$ and density is $8\times {10}^3 \mathrm{kg} {\mathrm{m}}^{-3}$. The velocity of longitudinal wave in the rod will be

• A

  $145.75\times {10}^3 \mathrm{m} {\mathrm{s}}^{-1}$
• B

  $3.65\times {10}^3 \mathrm{m} {\mathrm{s}}^{-1}$
• C

  $18.96\times {10}^3 \mathrm{m} {\mathrm{s}}^{-1}$
• Correct answer
  D

  $6.32\times {10}^3 \mathrm{m} {\mathrm{s}}^{-1}$

Hence, the correct answer is option: 'D'.