In photoelectric effect, the stopping potential (V₀) v / s frequency (v) curve is plotted.
( h is the Planck's constant and φ₀ is work function of metal )
(A) V₀ v / s v is linear.
(B) The slope of V₀ v / s v curve =φ₀/h
(C) h constant is related to the slope of V₀ v / s v line.
(D) The value of electric charge of electron is not required to determine h using the V₀ v / s v curve.
(E) The work function can be estimated without knowing the value of h.
Choose the correct answer from the options given below :

Solution

Physics sir · 3 steps

Write Einstein's equation as V₀ against ν, and each statement becomes a slope or intercept check.

1. Einstein's equation. The fastest electron's kinetic energy equals eV₀, so eV₀ = hν - φ₀. Divide by e to get V₀ alone.

   V₀ = (h/e)ν - φ₀/e

2. Read the line. This has the form y = mx + c. The slope is h/e and the intercept on the V₀ axis is -φ₀/e.

   Statement	Verdict	Reason
   (A) Linear	True	V₀ is a first-power function of ν
   (B) Slope = φ₀/h	False	Slope is h/e
   (C) h linked to slope	True	h = e × slope
   (D) e not needed for h	False	You must multiply the slope by e
   (E) φ₀ without h	True	V₀-intercept is -φ₀/e, so φ₀ in eV equals the size of the intercept in volts

3. So. Only (A), (C) and (E) are correct, which is option (a).

The idea to keep. For the V₀ against ν graph, the slope is h/e for every metal. The V₀-intercept is -φ₀/e, and the ν-intercept is the threshold frequency.

Answer from the NTA final answer key. Solution by PrepWiser.