Moderate

The uncertainty in momentum & position is due to its_____________?

Correct answer: A. Property of matter and radiation

  • A. Property of matter and radiation
  • B. Two-dimensional motion
  • C. Emission of the certain wavelength
  • D. Very high velocity

Explanation

The uncertainty in position and momentum is an intrinsic wave-particle property of matter and radiation, expressed by Δx Δp >= h/(4π). It is not caused merely by high speed, two-dimensional motion, or emission of a particular wavelength. Students may choose high velocity because large momentum feels difficult to measure, but uncertainty exists even when the average velocity is small.

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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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