Light of wavelength 1824 ∘A, incident on the surface of a metal, produces photo-electrons with maximum energy 5.3 eV. When light of wavelength 1216 ∘A is used, the maximum energy of photoelectrons is 8.7 eV. The work function of the metal surface is
1.5 eV
E=W0+Kmax From the given data E is 6.78 eV (for λ=1824 ∘A) or 10.17 eV (for λ=1216 ∘A)
∴ W0=E−Kmax=6.78−5.3=1.48eV
or
W0=10.17−8.7=1.47 eV