Difficulty: Easy
Correct Answer: True
Explanation:
Introduction / Context:
The Bohr model, though superseded by quantum mechanics, provides an intuitive picture of hydrogenic orbits. It relates electrostatic attraction to centripetal requirements for circular motion, combined with angular-momentum quantization, to explain discrete energy levels and spectral lines.
Given Data / Assumptions:
Concept / Approach:
For a circular orbit, the centripetal force m v^2 / r must be supplied by Coulomb attraction k e^2 / r^2 (with k = 1/(4π ε0), e the elementary charge). Equating these gives the relationship among m, v, and r. Combined with the angular momentum postulate, one solves for allowed radii r_n and energies E_n. This balance is the physical “stability” condition in the Bohr picture.
Step-by-Step Solution:
Verification / Alternative check:
In full quantum mechanics, the expectation values match Bohr predictions for hydrogen energy levels, validating the historical model’s results though not its orbital picture.
Why Other Options Are Wrong:
Limiting the validity to n = 1 or T = 0 is unnecessary in the Bohr framework; relativistic corrections are small and not required for the primary stability condition.
Common Pitfalls:
Confusing “stability” here with quantum stability; Bohr’s circular orbit analogy is a semi-classical construction leading to correct spectra despite its limitations.
Final Answer:
True
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