Question

The wavelength of a spectral line of casium is 460 mm. Calculate the frequency of the Iine.​

Answer 1

$\bull\sf Wavelength=\lambda=460mm=4.6\times 10^{-6}m$

• Frequency=v=?

We know

$\boxed{\sf \lambda=\dfrac{c}{v}}$

$\\ \sf\longmapsto v=\dfrac{c}{\lambda}$

$\\ \sf\longmapsto v=\dfrac{3\times 10^{8}ms^{-1}}{4.6\times 10^{-6}m}$

$\\ \sf\longmapsto v=0.652\times 10^{14}s^{-1}$

$\\ \sf\longmapsto v=6.52\times 10^{13}Hz$