Atoms - Result Question 22

23. An electron in the hydrogen atom jumps from excited state $n$ to the ground state. The wavelength so emitted illuminates a photosensitive material having work function $2.75 eV$. If the stopping potential of the photoelectron is $10 V$, the value of $n$ is

«««< HEAD

======= ####23. An electron in the hydrogen atom jumps from excited state $n$ to the ground state. The wavelength so emitted illuminates a photosensitive material having work function $2.75 eV$. If the stopping potential of the photoelectron is $10 V$, the value of $n$ is

c3eec34ec6b1fad69db54a20ad4b2dca40c2aa54 (a) 3

(b) 4

(c) 5

(d) 2

[2011M]

Show Answer

Answer:

Correct Answer: 23. (b)

Solution:

  1. (b) $KE _{\max }=10 eV$

$\phi=2.75 eV$

Total incident energy

$E=\phi+KE _{\max }=12.75 eV$

$\therefore$ Energy is released when electron jumps from the excited state $n$ to the ground state.

$\because E_4-E_1={-0.85-(-13.6) ev}$

$=12.75 eV$

$\therefore$ value of $n=4$



NCERT Chapter Video Solution

Dual Pane