Question

A quantity $X$ is given by $\frac{m{e}^4}{8{\epsilon }_0^{2}c{h}^3},$ where $m$ is the mass of electron, $e$ is the charge of electron, ${\epsilon }_0$ is the permittivity of free space, $c$ is the velocity of light and $h$ is the Planck's constant. The dimensional formula for $X$ is the same as that of

• A. length
• B. frequency
• C. velocity
• D. wave number

Answer 1

Answer: (D)

$X=\frac{m{e}^4}{8{\epsilon }_0^{2}c{h}^3}=$
Rydberg's constant and its unit is $m^{-1}$