5.6.167 - Hertzsprung-Russell diagram

Be able to sketch and interpret a simple Hertzsprung-Russell diagram that relates stellar luminosity to surface temperature.

Use - hertzsprung-russell diagram to connect the rule to the data and decision in the question.

This matters because - hertzsprung-russell diagram determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply - hertzsprung-russell diagram to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: - Hertzsprung-Russell diagram is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.