Asked in MDCAT Test Series — Dawn of Modern Physics and Nuclear PhysicsModerate

According to quantum theory the radiation must appear in the form of:

Correct answer: C. Photons

  • A. Electrons
  • B. Protons
  • C. Photons
  • D. Neutrons

Explanation

According to quantum theory, radiation must appear in the form of discrete packets of energy called quanta (or photons).Here's a breakdown:Classical Physics (before quantum theory): Classical physics described light as a continuous wave. This model couldn't explain certain phenomena like blackbody radiation and the photoelectric effect.Quantum Theory: Max Planck proposed that energy is not emitted or absorbed continuously but in discrete packets called quanta. Albert Einstein later extended this idea to light itself, suggesting that light consists of particles called photons, each carrying a specific amount of energy.The energy of a photon is given by the equation:E = hf

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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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