Atoms And Nuclei Question 270

Question: The acceleration of an electron in the first orbit of the hydrogen atom (z=1) is:

Options:

A) $ \frac{h^{2}}{{{\pi }^{2}}m^{2}r^{3}} $

B) $ \frac{h^{2}}{8{{\pi }^{2}}m^{2}r^{3}} $

C) $ \frac{h^{2}}{4{{\pi }^{2}}m^{2}r^{3}} $

D) $ \frac{h^{2}}{4\pi m^{2}r^{3}} $

Show Answer

Answer:

Correct Answer: C

Solution:

  • Speed of electron in first orbit (n=1) of hydrogen atom (z=1), $ v=\frac{e^{2}}{2{\varepsilon_{0}}h} $ $ r=\frac{h^{2}{\varepsilon_{0}}}{\pi me^{2}}\Rightarrow {\varepsilon_{0}}=\frac{r\pi me^{2}}{h^{2}} $
    Acceleration of electron,

    $ \frac{v^{2}}{r}=\frac{e^{4}}{4\varepsilon_0^{2}h^{2}}\times \frac{\pi me^{2}}{h^{2}{\varepsilon_{0}}} $

    $ \frac{e^{4}\times \pi me^{2}}{4h^{4}\varepsilon _{0}^{3}} $

    Eliminating $ {\varepsilon_{0}} $ $ =\frac{e^{4}\pi me^{2}h^{6}}{4h^{4}r^{3}{{\pi }^{3}}m^{3}e^{6}}=\frac{h^{2}}{4{{\pi }^{2}}m^{2}r^{3}} $



NCERT Chapter Video Solution

Dual Pane