Q52. The value of Rydberg constant $\left( R _ { H } \right)$ is $2.18 \times 10 ^ { - 18 } \mathrm {~J}$. The velocity of electron having mass $9.1 \times 10 ^ { - 31 } \mathrm {~kg}$ in Bohr's first orbit of hydrogen atom $=$ $\_\_\_\_$ $\times 10 ^ { 5 } \mathrm {~ms} ^ { - 1 }$ (nearest integer).