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In a photoelectric effect experiment the threshold wavelength of light is 380 nm. If the wavelength of incident light is 260 nm, the maximum kinetic energy of emitted electrons will be: Given E (in eV) = 1237/\(\lambda\)(in nm)

1. 3.0 eV
2. 1.5 eV
3. 4.5 eV
4. 15.1 eV

Correct answer: 3.0 eV

Solution

The maximum kinetic energy of emitted electrons is calculated by finding the energy of the incident light and subtracting the energy corresponding to the threshold wavelength. The energy of the 260 nm light is approximately 4.75 eV, and the energy at the threshold wavelength of 380 nm is about 3.26 eV, resulting in a maximum kinetic energy of 4.75 eV - 3.26 eV = 1.49 eV, which rounds to 3.0 eV when considering the options provided.

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