Question

When the energy of the incident radiation is increased by `20 %` , kinetic energy of the photoelectrons emitted from a metal surface increased from `0.5 eV to 0.8 eV`. The work function of the metal is
A. 0.65 eV
B. 1.0 eV
C. 1.3 eV
D. 1.5 eV

Answer 1

Correct Answer - B
`KE_(max) = hv - Psi` ….(A)
`0.5 eV = hv - Psi` …(B)
`0.8 eV = 1.2 hv - Psi`
solving `Psi = 1 eV`.