Photoelectrons are ejected from a cesium surface ( = 1.9 eV ) by a beam of monochromatic light of wavelength . These photoelectrons are subsequently directed to collide with hydrogen atoms in the ground state. Determine the maximum value of such that the hydrogen atoms may be ionized.

Step-by-step solution

The minimum kinetic energy required by a photoelectron to ionize a hydrogen atom in its ground state is equal to the ionization energy of hydrogen, which is 13.6 eV . According to Einstein's photoelectric equation, the maximum kinetic energy of the ejected photoelectrons is given by K_ max = hc - For the photoelectrons to be able to ionize the hydrogen atoms, their kinetic energy must be at least 13.6 eV . Therefore, hc - 13.6 eV Substituting the given work function of cesium = 1.9 eV , hc - 1.9 eV 13.6 eV hc 15.5