CBSE Class 12 · 2017 · Modern PhysicsVery Short Answer

State one factor which determines the intensity of light in the photon picture of light.

Answer: Number of photons incident per unit area per unit time.

Solution

In the photon picture the intensity is fixed by the number of photons crossing unit area per unit time (the photon flux) — more photons per second per unit area means greater intensity.

Number of photons incident per unit area per unit time

CBSE Class 12 Board · 2017 · Subjective

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