Ultraviolet light of 200 nm wavelength is incident on polished surface of iron .Its work function is 4.71 eV what will be value of stopping potential?[h=6.626xx10^(-34)]JSc=3xx10^(8)m//s1eV=1.6xx10^(-19)J ]

Ultraviolet light of 200 nm wavelength is incident on polished surface

1.	Ultraviolet light of 200 nm wavelength is incident on polished surface of iron .Its work function is 4.71 eV what will be value of stopping potential?[h=6.626xx10^(-34)]JSc=3xx10^(8)m//s1eV=1.6xx10^(-19)J ]
Answer» 0.5V 1.5 V 2.5 V None of these Solution :`eV_(0)=hf-phi` `V_(0)=(hc)/(lambdae)-(phi)/(E )` `=(6.626xx10^(-34)xx3xx10^(8))/(2XX10^(-7)xx1.6xx10^(-198))-(4.71e)/(e )`

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Ultraviolet light of 200 nm wavelength is incident on polished surface of iron .Its work function is 4.71 eV what will be value of stopping potential?[h=6.626xx10^(-34)]JSc=3xx10^(8)m//s1eV=1.6xx10^(-19)J ]

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