CBSE Class 12 · 2019 · Modern PhysicsVery Short Answer

Define the term "Intensity" in the photon picture of electromagnetic radiation.

Answer: Energy (number of photons $\times h ν$ ) incident per unit area per unit time.

Solution

In the photon picture the intensity of radiation is the energy incident per unit area per unit time, which equals the number of photons crossing unit area per unit time multiplied by the energy

h ν

of each photon.

Intensity = photon energy h ν \times photon flux

CBSE Class 12 Board · 2019 · Subjective

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