Year 11 - Science
Emitting infrared radiation
Electromagnetic waves
Study Hub
Study Guides
This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
This unit explores reflection, refraction, and lenses using ray diagrams. It covers the electromagnetic spectrum, light as a wave, absorption, transmission, and practical uses. Emphasis is on risks, temperature balance, data presentation, and unit conversions.
Lesson Summary
You will learn to describe how to investigate the emission of infrared radiation by different surfaces.
Key Notes
- All bodies (objects) of all temperatures emit and absorb infrared radiation. Hotter bodies emit more IR in a set time.
- The range of wavelengths emitted, and their intensities, depend on an object's temperature.
- Good absorbers (e.g. dark and dull surfaces) are also good emitters. Shiny metal surfaces are poor absorbers/emitters.
Vocabulary To Learn
- infrared radiation: Infrared radiation means electromagnetic waves with frequencies in a range just lower than for red light.
- emit: To emit infrared radiation is to give out infrared radiation.
- temperature: The temperature of an object measures how hot or cold it is.
- Leslie cube: A Leslie cube is a hollow metal cube that can be filled with hot water. Each side has a different colour and finish so emits different intensities of infrared radiation.
Common Mistakes To Avoid
- White surfaces are always poor absorbers of visible light so they must also always be poor absorbers and emitters of infrared.
3 Quick Questions (With Answers)
1. Explain the scientific idea in this lesson using two key points.
All bodies (objects) of all temperatures emit and absorb infrared radiation. Hotter bodies emit more IR in a set time. The range of wavelengths emitted, and their intensities, depend on an object's temperature.
2. Define this scientific word and use it in context. 'infrared radiation'
Infrared radiation means electromagnetic waves with frequencies in a range just lower than for red light. Include the word in a full scientific explanation, not as a single label.
3. Correct this common scientific misunderstanding.
Mistake: White surfaces are always poor absorbers of visible light so they must also always be poor absorbers and emitters of infrared. Correction: White paint is a good absorber and emitter of IR. Colour is not always a good guide to effectiveness at emitting/absorbing IR, except for dark+dull surfaces usually being good emitters/absorbers and shiny metal surfaces being poor emitters/absorbers.
More Lessons In This Unit
- Absorbing infrared radiation practical Study Guide
- Converging lenses Study Guide
- Convex lenses Study Guide
- Convex lenses (including magnification) Study Guide
- Dispersion of light and electromagnetic radiation Study Guide
- Dispersion of light and electromagnetic waves Study Guide
- Emitters of infrared & black body radiation Study Guide
- Emitting infrared and black body radiation Study Guide
- Ionising electromagnetic radiation Study Guide
- Light and colour Study Guide
- Non-ionising electromagnetic radiation Study Guide
- Non-ionising electromagnetic radiations Study Guide
- Reflection of light Study Guide
- Reflection of light (including specular and diffuse) Study Guide
- Refraction through a rectangular block Study Guide
- Refraction through a rectangular block (including wave front diagrams) Study Guide
- Refraction through a semicircular block Study Guide
- Refraction through a semicircular block (including TIR) Study Guide
- Scale diagrams for converging lenses Study Guide
- Scale diagrams for convex lenses Study Guide
- Scale diagrams for convex lenses (including magnification) Study Guide
- The spectrum of electromagnetic radiation Study Guide
- The spectrum of electromagnetic waves Study Guide
- Virtual images from converging and diverging lenses Study Guide
- Virtual images from convex and concave lenses Study Guide
- Virtual images from convex and concave lenses (including magnification) Study Guide
Browse all guides in the Year 11 Science guide library.