The molecules of a given mass of gas have RMS velocity of $200$ $\mathrm{m }{\mathrm{s}}^{-1}$ at ${27}^{\mathrm{o}}\mathrm{C}$ and $1.0\times {10}^5\mathrm{ }\mathrm{N }{\mathrm{m}}^{-2}$ pressure. When the temperature and pressure of the gas are respectively, ${127}^{\mathrm{o}}\mathrm{C}$ and $0.05\times {10}^5\mathrm{ }\mathrm{N }{\mathrm{m}}^{-2}$, the r.m.s. velocity of its molecules in $\mathrm{m }{\mathrm{s}}^{-1}$ is:

• A

  $100\sqrt{2}$
• Correct answer
  B

  $\frac{400}{\sqrt{3}}$
• C

  $\frac{100\sqrt{2}}{3}$
• D

  $\frac{100}{3}$

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