In a sample of excited hydrogen atoms electrons make transition from n = 2 to n = 1. Emitted photons striķe on a metal of work function (phi) 4.2 eV. Calcualte the wavelength (in A^@) associated with ejected electrons having maximum kinetic energy.

In a sample of excited hydrogen atoms electrons make transition from n

1.	In a sample of excited hydrogen atoms electrons make transition from n = 2 to n = 1. Emitted photons striķe on a metal of work function (phi) 4.2 eV. Calcualte the wavelength (in A^@) associated with ejected electrons having maximum kinetic energy.
Answer» Solution :`n_2 to n_1 , E = hc BARV = hcR (1/(n_1^2) - 1/(n_2^2))` = hcR (3/4) K.E. hcR (3/4) - 4.2 EV On SOLVING `lambda = 5A^0`