Start free

Physics · Atomic Physics

JEE Main 2025 — 24 January, Evening Shift — Question 57

In photoelectric effect, the stopping potential (V0)\left(\mathrm{V}_{0}\right) v/s\mathrm{v} / \mathrm{s} frequency ( v ) curve is plotted.

(h is the Planck's constant and ϕ0\phi_{0} is work function of metal)

(A) V0v/svV_{0} v / s v is linear

(B) The slope of V0v/sv\mathrm{V}_{0} \mathrm{v} / \mathrm{s} v curve =ϕ0 h=\frac{\phi_{0}}{\mathrm{~h}}

(C) h constant is related to the slope of V0v/sv\mathrm{V}_{0} \mathrm{v} / \mathrm{s} \mathrm{v} line

(D) The value of electric charge of electron is not required to determine hh using the V0v/svV_{0} v / s v curve.

(E) The work function can be estimated without knowing the value of hh.

Choose the correct answer from the options given below :

  1. Option A:

    (A),(B) and (C) only

  2. Option B:

    (C) and (D) only

  3. Option C:

    (A),(C) and (E) only

    Correct
  4. Option D:

    (D) and (E) only

Answer: C

Step-by-step solution

hv=ϕ+KEmax \mathrm{hv}=\phi+\mathrm{KE}_{\text {max }}

KEmax =eV0\mathrm{KE}_{\text {max }}=\mathrm{eV}_{0}

V0=hv−ϕe\mathrm{V}_{0}=\frac{\mathrm{hv}-\phi}{\mathrm{e}}

(A) V0v/sV\mathrm{V}_{0} \mathrm{v} / \mathrm{s} \mathrm{V} is linear correct

(B) Slope

v0=(he)v−ϕe\mathrm{v}_{0}=\left(\frac{\mathrm{h}}{\mathrm{e}}\right) \mathrm{v}-\frac{\phi}{\mathrm{e}} Wrong

Slope he\frac{h}{\mathrm{e}}

(C) Correct

(D) Incorrect

(E) Correct

Answer key and solution verified before publishing.

Practise Atomic Physics

Start with this question, then two more from the same chapter — with a tutor that explains every step. Free.

Solve a similar one free
Exam
JEE Main 2025
Paper
24 January, Evening Shift
Subject
Physics
Chapter
Atomic Physics
Topic
Photoelectric Effect

More Atomic Physics questions from this paper