The maximum wavelength of radiation that can produce photoelectric effect in a certain metal is 200 nm. The maximum kinetic energy acquired by electron due to radiation of wavelength 100 nm will be

Question

The maximum wavelength of radiation that can produce photoelectric effect in a certain metal is 200 nm. The maximum kinetic energy acquired by electron due to radiation of wavelength 100 nm will be (A) 12.4 eV (B) 6.2 eV (C) 100 eV (D) 200 eV

Tardigrade Admin · Accepted Answer

Given, λ max =200 mn =2 × 10-7 m ∴ Work function (W)=(h c/λ max )=(6.6 × 10-34 × 3 × 108/2 × 10-7) =9.9 × 10-19 J =6.19 eV Energy of photon of wavelength 100 nm E=(h c/λ)=(6.6 × 10-34 × 3 × 108/1 × 10-7) =19.8 × 10-19 J= 12.37 eV ∴ Maximum KE of photoelectron =E-W=12.37-6.19=6.18 eV ≈ 6.2 eV

Q. The maximum wavelength of radiation that can produce photoelectric effect in a certain metal is 200nm. The maximum kinetic energy acquired by electron due to radiation of wavelength 100nm will be

12.4 eV

6.2 eV

100 eV

200 eV

Given, λmax​=200mn=2×10−7m ∴ Work function (W)=λmax​hc​=2×10−76.6×10−34×3×108​ =9.9×10−19J=6.19eV Energy of photon of wavelength 100nm E=λhc​=1×10−76.6×10−34×3×108​ =19.8×10−19J=12.37eV ∴ Maximum KE of photoelectron =E−W=12.37−6.19=6.18eV≈6.2eV

Q. The maximum wavelength of radiation that can produce photoelectric effect in a certain metal is $200 nm$ . The maximum kinetic energy acquired by electron due to radiation of wavelength $100 nm$ will be