JEE Advanced 2014 Paper 2 Physics Q7

Physics · Dual Nature of Radiation & Matter

Problem

A metal surface is illuminated by light of two different wavelengths

248\,\mathrm{nm}

and

310\,\mathrm{nm}

. The maximum speeds of the photoelectrons corresponding to these wavelengths are

u_1

and

u_2

, respectively. If the ratio

u_1:u_2=2:1

and

hc=1240\,\mathrm{eV\,nm}

, the work function of the metal is nearly