From Einstein's photoelectric equation, hν=ϕ+eV0.
⇒V0=ehν−eϕ......(1)
At ν=4×1014Hz, V0=0.
Putting the value in equation (1), we get
0=ehv−eϕ
So, Work function (ϕ)=e(hν)(ineV)
=1.6×10−196.63×10−34×(4×1014)
=1.66eV
The stopping potential V_o (in volt) as a function of frequency (v) for a sodium emitter, is shown in the figure. The work function of sodium, form…
JEE Main 2019 — Physics Modern Physics
2019mcqeasy
The stopping potential Vo (in volt) as a function of frequency (v) for a sodium emitter, is shown in the figure. The work function of sodium, form the data plotted in the figure, will be:
(Given: Planck’s constant (h)=6.63×10−34Js , electron charge (e) =1.6×10−19C)
Official previous-year question
Held on 12 Apr 2019 · Verified 6 Jul 2026.
Options
- A
2.12eV
- B
1.82eV
- C
1.95eV
- D
1.66eV
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