Target Exam

CUET

Subject

Physics

Chapter

Atoms

Question:

The minimum energy required to excite a Hydrogen atom from its ground state is:

Options:

10.2 eV

13.6 eV

3.4 eV

6.28 eV

Correct Answer:

10.2 eV

Explanation:

The correct answer is Option (1) → 10.2 eV

For a hydrogen atom, the energy levels are given as -

$E_n=-\frac{13.6eV}{n^2}$

for $n=1$ (ground state)

$E_1=-\frac{13.6}{(1)^2}=-13.6eV$

for $n=2$ (first excited state)

$E_2=-\frac{13.6}{(2)^2}=-3.4eV$

$∴ΔE=E_2-E_1=10.2eV$