RevTree
#83

4.6.2.7 Visible Light

Paper 2 · Higher combined

Spec reference: 4.6.2 (subtopic).

What you need to know

  • visible light Used for lighting, photography and fibre optics. Frequency range that is detectable by the human eye.
  • ultraviolet Sterilising water and killing bacteria. Detecting
  • forged bank notes.
  • Causes skin tanning and can lead to burns or skin cancer.
  • X-rays Medical imaging and airport security scanners. Very little energy is absorbed by body tissues. Instead, it is transmitted
  • through the body.
  • These waves can lead to gene mutation and cancer.
  • gamma rays Sterilising medical equipment or food and

Self-assessment (checklist)

  • I can explain which properties of each colour within
  • I can explain what is meant by specular reflection.
  • I can explain what is meant by diffuse reflection.
  • I can explain how colour filters work.
  • I can explain how the colour of an object is related to
  • I can explain the effect of viewing objects through
  • I can explain why an opaque object has a particular
  • I can explain what is meant by the terms transparent

Key steps (method)

  • Identify what the question is testing and use the correct equation/definition.
  • Show substitutions and units clearly.

Common mistakes

  • Unit conversions, rearranging errors, or quoting a law without applying it.