EnergyDiagram

Black Body Spectrum

Part of Black Body Radiation · GCSE GCSE Physics revision

This diagram covers Black Body Spectrum within Black Body Radiation for GCSE Physics. Revise Black Body Radiation in Energy for GCSE Physics with 16 exam-style questions and 5 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 3 of 7 in this topic. Focus on the labels, the relationships between parts, and the explanation that turns the diagram into an exam-ready answer.

Topic position

Section 3 of 7

Practice

16 questions

Recall

5 flashcards

📊 Black Body Spectrum

ECharts graph showing black body radiation intensity vs wavelength (200–1400 nm) for three temperatures. The 3000 K red curve peaks at 966 nm in the infrared. The 4500 K amber curve peaks at 644 nm in the visible red. The 6000 K cyan curve peaks at 483 nm in the blue-green visible range. A violet shaded band marks the visible light region 380–700 nm. All curves are normalised to their own peak. Peak wavelength markers show Wien's law shift.

Figure 2: Black body spectrum — as temperature rises the peak shifts to shorter wavelengths (Wien's Law) and total emission increases.

All objects emit a continuous spectrum of EM radiation. The intensity and peak wavelength depend on TEMPERATURE.

KEY OBSERVATIONS:

  • Higher temperature → MORE total radiation emitted (curve gets taller/larger area)
  • Higher temperature → SHORTER peak wavelength (curve shifts left towards blue/UV)
  • Higher temperature → different visible colour:
TemperaturePeak EmissionColour Appearance
Cold objectsInfraredInvisible (dark)
~1000°CNear-infrared/redDull red glow
~3000°CRed/orangeBright orange/yellow
~6000°C (Sun)Visible (all colours)White
~10000°C+Blue/UVBlue-white

Keep building this topic

Read this section alongside the surrounding pages in Black Body Radiation. That gives you the full topic sequence instead of a single isolated revision point.

Practice Questions for Black Body Radiation

What is a perfect black body?

  • A. An object that reflects all radiation that hits it
  • B. An object that only emits visible light
  • C. An object that absorbs all radiation that hits it and reflects none
  • D. An object that is black in colour and absorbs only visible light
1 markfoundation

Explain how the radiation emitted by an object changes as its temperature increases.

3 marksstandard

Quick Recall Flashcards

Define:
A black body is a theoretical perfect absorber and perfect emitter of radiation.
Perfect emitter
Emits the maximum amount of radiation at every wavelength

16 questions on Black Body Radiation — practise free

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