25.1.2—The inverse square law for radiant flux intensity F

recall and use the inverse square law for radiant flux intensity F in terms of the luminosity L of the source F = L / (4πd 2).

Use —the inverse square law for radiant flux intensity f to connect the rule to the data and decision in the question.

This matters because —the inverse square law for radiant flux intensity f determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the inverse square law for radiant flux intensity f to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The inverse square law for radiant flux intensity F is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.