TS EAMCET 19-July-2022 Shift 2 Solved Paper

For the occurrence of photoelectric effect, a minimum amount of energy, i.e. equal to work function (φ) is to be given to an electron.
The metals having lower values of work function than the incident energy values will show photoelectric effect.
Incident energy can be calculated as
E=‌

hc

λ

where, E= energy,
h‌=‌ Planck's constant ‌(6.63×10−34‌Js)
c‌=‌ speed of light ‌(3×108m∕ s)
λ‌=‌ wavelength ‌(300‌nm)
E‌=‌

6.63×10−34×3×108

300×10−9m×1.6×10−19

‌eV
‌=4.14‌eV

Metal	Li	Mg	Ag	Cu	K
(\ϕ)eV	2.4	3.7	4.3	4.8	2.2

Here, we can see that Li,Mg and K have lower value of φ than incident energy. Therefore, they will show photoelectric effect.