What this topic covers
Topic 5: Light and the electromagnetic spectrum has 2 subtopics:
- Light rays, lenses and electromagnetic waves
- Thermal radiation and surface effects
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GCSE Edexcel Higher Physics · Topic 5 of 15
Topic 5: Light and the electromagnetic spectrum – GCSE Edexcel Higher Physics revision notes
Choose a subtopic. Light, lenses, the electromagnetic spectrum and thermal radiation. 19 lessons in 2 subtopics.
Revise Topic 5: Light and the electromagnetic spectrum for GCSE Edexcel Higher Physics, including Light rays, lenses and electromagnetic waves.
19
Lessons
2
Subtopics
Topic 5: Light and the electromagnetic spectrum lessons by subtopic
19 lessons, grouped by subtopic.
Light rays, lenses and electromagnetic waves
- Introduction to Electromagnetic Waves: Discover the nature of electromagnetic waves and their properties.
- The Electromagnetic Spectrum: Explore the different types of electromagnetic waves, their order in the spectrum, and the limited range of visible light.
- EM Wave Interactions with Matter: Explore how different substances interact with electromagnetic waves through absorption, transmission, refraction, and reflection, depending on the wavelength.
- Refraction and Wave Velocity: Understand how refraction occurs due to changes in the velocity of electromagnetic waves as they move between different substances.
- Producing and Absorbing Radio Waves and Gamma Rays
- Hazards of UV, X-rays, and Gamma Rays
- Radio Waves, Microwaves and Infrared
- Visible Light, Ultraviolet, X-Rays, and Gamma Rays: Discover the applications of visible light, ultraviolet, X-rays, and gamma rays in fiber optics, energy-efficient lighting, medical imaging, and treatments.
- Convex and Concave Lenses
- Ray Diagrams
- Magnification
- Visible Light: Absorption, Reflection, and Transmission
- Colour Filters & Wavelengths
- Light rays, refraction, lenses and image formation: Use ray diagrams for reflection, refraction, total internal reflection, lenses and image formation.
- How atoms and nuclei generate or absorb radiation: Recall that atomic and nuclear changes can produce or absorb radiation across a wide frequency range.
Thermal radiation and surface effects
- Infrared Radiation: Emission and Absorption
- Emission and Absorption
- Earth's Temperature and Radiation Balance
- Core practical: thermal radiation from different surfaces: Investigate how surface type affects the rate of thermal radiation absorption or emission.
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Frequently asked questions
What is Topic 5: Light and the electromagnetic spectrum?
Light, lenses, the electromagnetic spectrum and thermal radiation. 19 lessons in 2 subtopics.
What is the magnification equation?
The magnification equation is magnification = image height ÷ object height. The Magnification notes cover this in full.
What is refraction of electromagnetic waves?
Refraction is the bending of electromagnetic waves when they pass from one medium to another, due to a change in wave speed. The EM Wave Interactions with Matter notes cover this in full.
What is the wavelength range of visible light?
Visible light ranges from red, with a wavelength of about 700 nanometres, to violet, with a wavelength of about 400 nanometres. The The Electromagnetic Spectrum notes cover this in full.
What are the wavelengths of visible light?
Visible light has wavelengths from approximately 400nm (violet) to 700nm (red). The Colour Filters & Wavelengths notes cover this in full.
How do you calculate magnification?
To calculate magnification, divide the image height by the object height using the same units. The Magnification notes cover this in full.
What are gamma rays used for?
Gamma rays are used in medical gamma cameras to image internal organs, using isotopes such as technetium-99m, and in industry to sterilise medical equipment and food products. The Producing and Absorbing Radio Waves and Gamma Rays notes cover this in full.
How do you draw a ray diagram?
A ray diagram starts with the lens, the principal axis and the focal points drawn with a ruler; the object is added as an arrow, then special rays that follow fixed rules are drawn. The Ray Diagrams notes cover this in full.
What are the three rays used in ray diagrams?
Ray diagrams use three special rays: a ray parallel to the principal axis refracts through (or appears to come from) the principal focus, a ray through the centre of the lens goes straight on, and a ray through the principal focus emerges parallel to the axis. The Ray Diagrams notes cover this in full.