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A particle of mass m moves in a circular orbit in a central potential field U(r) = \frac{1}{2} k r^{2} . If Bohr's quantization conditions are applied, radii of possible orbitals and energy levels vary with quantum number n as :

  • Option 1)

     r_{n} \ \alpha \ \sqrt{n} , E_{n} \ \alpha \ \frac{1}{n}

  • Option 2)

     r_{n} \ \alpha \ n , E_{n} \ \alpha \ n

  • Option 3)

    r_{n} \ \alpha \ \sqrt{n} , E_{n} \ \alpha \ n

  • Option 4)

     r_{n} \ \alpha \ n^{2} , E_{n} \ \alpha \ \frac{1}{n^{2}}

Answers (1)

best_answer

 

Hypothetical atomic model -

\left | \frac{dU}{dr} \right |= \frac{mv^{2}}{r}

mvr= \frac{nh}{2\pi }

- wherein

Solve these two equations to get radius and energy of hypothetical atoms

 

F=\frac{-du}{dr}

U=\frac{1}{2}kr^{2}

F=\frac{1}{2}\times 2\times kr=kr

F=\frac{mv^{2}}{r}=kr

So v^{2}\alpha\, r^{2}

v\alpha\, r

& form both quantisation principle

mv r=\frac{nh}{2\pi }

So vr\, \, \alpha\, \, n

\Rightarrow r^{2}\,\alpha \, n

\Rightarrow r\,\alpha \, \sqrt{n}

now U =E=\frac{1}{2}kr^{2}

       U \alpha \, r^{2}

      U \alpha \, n

     E \alpha \, n


Option 1)

 r_{n} \ \alpha \ \sqrt{n} , E_{n} \ \alpha \ \frac{1}{n}

Option 2)

 r_{n} \ \alpha \ n , E_{n} \ \alpha \ n

Option 3)

r_{n} \ \alpha \ \sqrt{n} , E_{n} \ \alpha \ n

Option 4)

 r_{n} \ \alpha \ n^{2} , E_{n} \ \alpha \ \frac{1}{n^{2}}

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