Energy of photon: $E = \frac{hc}{\lambda} = \frac{1240}{200} = 6.2\,\text{eV}$
$$KE_{\max} = E - \phi = 6.2 - 4.2 = 2.0\,\text{eV}$$
Back to JEE Main 2022 Modern Physics
JEE Main 2022 — Physics Modern Physics
medium
mcq
2022
Official previous-year question
Verified 30 May 2026.
Question
The work function of a metal is $4.2\,\text{eV}$. The maximum kinetic energy of photoelectrons when light of wavelength $200\,\text{nm}$ falls on it is:
Options
- A
$2.0\,\text{eV}$
- B
$1.6\,\text{eV}$
- C
$2.4\,\text{eV}$
- D
$1.0\,\text{eV}$
Solution
Did you get this right?
Sign in to track your attempts and accuracy.
Your note
Sign in to keep a private note on this question. Nothing you write is ever public.
JEE Main Modern Physics in other years
More JEE Main Modern Physics Questions
The work function of a metal is 4.2 eV. The threshold wavelength for photoelectric emission is approximately:
2026
medium
mcq
The de Broglie wavelength of a particle with mass m and velocity v is:
2025
hard
mcq
The work function of a metal is 4.2 eV. What is the threshold wavelength for photoelectric emission? (hc = 1240 eV·nm)
2025
medium
mcq
The work function of a metal is 4.2 eV. The threshold wavelength is (hc = 1240 eV·nm):
2023
medium
mcq
In Bohrs model the ratio of the kinetic energy to the total energy of the electron in nth orbit is:
2023
hard
mcq