Question

Radius of the first orbit in H-atom is a0. Then, deBroglie wavelength of electron in the third orbit is

• A. 3πa0
• B. 6πa0
• C. 9πa0
• D. 12πa0

Answer 1

Answer: (B)

6πa0

Answer 2

The correct answer is option (B): 6πa0

$(r_3)_H=\frac{a_0 n^2}{Z}=a_0\times 3^2=9a_0$

$2\pi r=n\lambda$

$\Rightarrow 2\pi\times9a_0=3\lambda$

$\Rightarrow \lambda=6\pi a_0$