TS EAMCET 11-Sep-2020 Shift 1 Solved Paper

According to Einstein's photoelectric equation,
EK=E−φ0
where, EK= kinetic energy,
E= energy of incident photon
and φ0= work function of metal surface.
⇒‌‌E=EK+φ0 ....(i)
When energy of incident photon is increased by 20%, then
⇒‌‌E′=1.2E
1.2E=EK′+φ0...(ii)
From Eqs. (i) and (ii), we get
‌

E

1.2E

=‌

EK+φ0

EK′+φ0

=‌

0.5+φ0

0.8+φ0

[∵EK=0.5eV and EK′=0.8eV]
⇒‌‌‌

5

6

=‌

0.5+φ0

0.8+φ0

4+5φ0=3+6φ0⇒φ0=1eV