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A nanocapacitor’s capacitance is expressed in a unit ‘u’ formed using the electric charge e, Bohr radius a0, Planck’s constant h, and the speed of light c. Which relation for u is correct?
- u = e² h / a0
- u = hc / (e² a0)
- u = e² c / (h a0)
- u = e² a0 / (hc)
Correct answer: u = e² a0 / (hc)
Solution
The correct option expresses capacitance in terms of fundamental constants, where the combination of charge, length, and constants correctly relates to the physical dimensions of capacitance, aligning with the principles of electromagnetism and quantum mechanics.
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