Question

If the energy difference between the ground state and excited state of an atom is $4.4\times {10}^{-19}J.$ The wavelength of photon required to produce this transition is

• A. $4.5\times {10}^{-7}m$
• B. $4.5\times {10}^{-7}nm$
• C. $4.5\times {10}^{-7}\mathring{A}$
• D. $4.5\times {10}^{-7}cm$

Answer 1

The correct option is A $4.5\times {10}^{-7}m$

Given,

Energy difference $=4.4\times {10}^{-19}$ $J$

$⟹\frac{hc}{\lambda }=h\nu =4.4\times {10}^{-19}$

$⟹\lambda =\frac{(6.626\times {10}^{-34})(3\times {10}^8)}{4.4\times {10}^{-19}}$

$⟹\lambda =4.5\times {10}^{-7}$ $m$

So, wavelength of photon emitted $=4.5\times {10}^{-7}$ $m$