The surface of a metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photo electrons was found to be 1.68 eV. The work function of the metal is (h_(c)=1240eV.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 photo electrons was found to be 1.68 eV. The work function of the metal is (h_(c)=1240eV.nm)
Answer» 1.41 eV 1.51eV 1.68eV 3.09 eV Solution :Here `lamda=400nm and K_(MAX)=1.68eV. " "THEREFORE` Energy of incident light photon `E=(hc)/(lamda)=(1240)/(400)eV=3.1eV` As `E=phi_(0)+K_(max),` hence `phi_(0)=E-K_(max)=3.1-1.68=1.42eV`

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The surface of a metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photo electrons was found to be 1.68 eV. The work function of the metal is (h_(c)=1240eV.nm)

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