AP EAMCET Engineering 26 Apr 2017 Shift 1 Paper

The energy is calculated as:
E=hcλ
=6.6×10−34Js×

3×108m∕s

300×10−9m

=

1.98×10−25

300×10−9 m

=6.6×10−19 J
The energy in eV is derived as:
1eV=1.602×10−19
Energy=

6.6×10−19

1.602×10−19

=4.119eV
The metals which are having less value of work function than the energy calculated, they can undergo photoelectric effect.
Therefore, metals are Mg,K and Na