Questions
Question 1
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State the position-momentum uncertainty relation.
Question 2
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What does \(\Delta x\) represent in the uncertainty relation?
Question 3
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What happens to minimum momentum uncertainty when a particle is localized more tightly?
Question 4
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An electron is localized to \(1.00\times10^{-10}\,\mathrm m\). Estimate the minimum \(\Delta p\).
Question 5
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If \(\Delta x\) is halved, what happens to the minimum \(\Delta p\)?
Question 6
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State a common approximate energy-time uncertainty relation.
Question 7
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A state has lifetime \(1.0\,\mathrm{ns}\). Estimate its minimum energy width.
Question 8
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Convert \(5.3\times10^{-26}\,\mathrm J\) to electronvolts.
Question 9
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Why is uncertainty not just poor measurement technique?
Question 10
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Estimate the kinetic-energy scale for an electron confined to \(0.100\,\mathrm{nm}\) using \(\Delta p=5.25\times10^{-25}\,\mathrm{kg\,m\,s^{-1}}\).
Question 11
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Derive \(\Delta p\ge\hbar/(2\Delta x)\) from the uncertainty relation.
Question 12
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Why does confinement raise the ground-state energy of a particle?
Question 13
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A particle is confined to a region twice as wide. How does the uncertainty-based confinement energy scale change?
Question 14
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Compare uncertainty effects for an electron and proton confined to the same length.
Question 15
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Why does a shorter excited-state lifetime imply a broader spectral line?
Question 16
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Derive the confinement energy scale \(K\sim\hbar^2/(2mL^2)\).
Question 17
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Explain why an electron cannot be exactly at rest inside a finite atom.
Question 18
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How does uncertainty help explain why atoms have finite size?
Question 19
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Why is energy-time uncertainty interpreted differently from position-momentum uncertainty?
Question 20
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Connect de Broglie waves and uncertainty in one explanation.