The surface of a metal is illuminated with the light of 400 nm. The kinectic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is (hc = 1240 eV nm)

The surface of a metal is illuminated with the light of 400 nm. The ki

1.	The surface of a metal is illuminated with the light of 400 nm. The kinectic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is (hc = 1240 eV nm)
Answer» 1.51 eV 1.68 eV 3.09 eV 1.42eV Solution :`(1)/(2)mv_("MAX")^(2)=(lambda_(c))/(lambda)-w_(0)` `w_(0)=(lambda_(c))/(lambda)-(1)/(2)mv_("max")^(2)` `=(1240)/(400)-1.68=1.41eV`

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The surface of a metal is illuminated with the light of 400 nm. The kinectic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is (hc = 1240 eV nm)

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