Uncertainty in Energy of a Photon
Correct answer: C. 6.6 *10^{-20} eV
- A. 4*10^7 joules
- B. 4*10^{17}eV
- C. 6.6 *10^{-20} eV
- D. 4 *times 10 joules
Explanation
Using the uncertainty principle, we find \(\Delta E \geq 3.315 \times 10^{-30}\) J. Converting to eV, we get \(\Delta E \approx 2.07 \times 10^{-11}\) eV, or \(6.6 \times 10^{-20}\) eV when rounded.
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About Quantum Theory and Radiation
Quantum theory treats electromagnetic radiation as packets of energy called photons, with energy proportional to frequency through E equals hf. The topic covers Planck's hypothesis, photon momentum, the photoelectric effect, threshold frequency, work function and wave particle duality, distinguishing quantised energy exchange from classical continuous radiation.
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