In photoelectric experiment energy of 2.48 eV irradiates a photo sensitive material. The stopping potential was measured to be 0.5 V. Work function of the photo sensitive material is :
- 0.5 eV
- 1.68 eV
- 2.48 eV
- 1.98 eV
The Correct Option is D
Solution and Explanation
The energy relation for the photoelectric effect is:
\[ eV_s = h\nu - \phi \]
where $eV_s$ is the stopping potential energy, $h\nu$ is the energy of incident photons, and $\phi$ is the work function.
Given: $h\nu = 2.48 \, \text{eV}, \, V_s = 0.5 \, \text{V}.$
\[ 0.5 = 2.48 - \phi \]
\[ \phi = 2.48 - 0.5 = 1.98 \, \text{eV}. \]
The work function of the material is $\phi = 1.98 \, \text{eV}.$
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