The potential difference that must be applied to stop the fastest photoelectrons emitted by a nickel surface, having work function 5.01 eV, when ultraviolet light of 200 nm falls on it, must be

The potential difference that must be applied to stop the fastest phot

1.	The potential difference that must be applied to stop the fastest photoelectrons emitted by a nickel surface, having work function 5.01 eV, when ultraviolet light of 200 nm falls on it, must be
Answer» `-2.4V` `1.2V` `2.4V` `-1.2V` Solution :For light of wavelength `lamda=200nm`, energy of photon `E=(HC)/(elamda) eV=(6.63xx10^(-34)xx3xx10^(8))/(1.6xx10^(-19)xx200xx10^(-9))=6.21eV` `THEREFORE K_(max)=E-phi_(0)=6.21eV-5.01eV=1.2eV` `therefore` Stopping potential=-1.2eV.

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The potential difference that must be applied to stop the fastest photoelectrons emitted by a nickel surface, having work function 5.01 eV, when ultraviolet light of 200 nm falls on it, must be

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