A sodium metal piece is illuminated with light of wavelength 0.3 `mum`. The work function of sodium is 2.46 eV. For this situation ,mark out the correct statement (s).A. The maximum kinetic energy of the ejected photoelectrons is 1.68 eVB. The cut-off wavelength for sodium is 505 nmC. The minimum photon energy of incident light for photoelectric effect to take place is 2.46 eVD. All of the above

A sodium metal piece is illuminated with light of wavelength 0.3 `mum`

1.	A sodium metal piece is illuminated with light of wavelength 0.3 `mum`. The work function of sodium is 2.46 eV. For this situation ,mark out the correct statement (s).A. The maximum kinetic energy of the ejected photoelectrons is 1.68 eVB. The cut-off wavelength for sodium is 505 nmC. The minimum photon energy of incident light for photoelectric effect to take place is 2.46 eVD. All of the above
Answer» Correct Answer - D `K_(max)=hv-phi` `=((6.63xx10^(-34)xx3xx10^(8))/(0.3xx10^(-6)xx1.6xx10^(-19))-2.46)eV` `=1.68eV` Cut-off wavelength, `lamda_0=(hc)/(phi)=505nm` The minimum energy required to eject the photo-electrons is equal to work function.

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