If the critical wavelength of tungs...
Question

# If the critical wavelength of tungsten is 2600A, what is the energy of a quantum at this wavelength in eV? Further, calculate the wavelength necessary to produce photo electrons from tungsten having twice the kinetic energy of those produced at 2200A.

JEE/Engineering Exams
Chemistry
Solution
63
5.0 (3 ratings)
Witical wareleng/n =w Wanclergan when ( k . E ) is nownal=w When ( k cdot epsilon ) is dowbled ( =w_{2} ) ( k in_{1}=frac{1}{w_{1}}-frac{1}{w_{0}}, k in_{2}=2 k E_{1} ) ( k in_{2}=frac{1}{w_{2}}-frac{1}{w_{0}}=frac{2}{w_{1}}-frac{2}{w^{0}} ) ( Rightarrow quad frac{1}{w_{2}}=frac{2}{w_{1}}-frac{1}{w} ) subtettuling values ( frac{1}{w^{2}}=frac{2}{2200}-frac{1}{2600}=frac{2600-1100}{2860000} ) ( frac{1}{w^{2}}=frac{1500}{2860000} Rightarrow w_{2}=frac{2860000}{1500} ) ( w_{2}=1906.667 )