The surface of a metal is illuminated with the light of 400 nm. The kinetic 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 kinetic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is (hc = 1240 eV nm)
Answer» 3.09 eV 1.42 eV 1.51 eV 1.68 eV Solution :`K_(max) = (hc)/(LAMBDA) - W_(0) or W_(0) = (hc)/(lambda) - K_(max)` `= (1240)/(400) - 1.68 = 3.10 - 1.68 = 1.42` eV

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