Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can define refraction and explain it as a result of the speed of light changing at a boundary. (Guide: “Why light bends”)
- I can explain why a ray that meets a boundary along the normal does not change direction. (Guide: “Why light bends”)
- I can state that a larger index of refraction means a lower speed of light, and that the frequency does not change. (Guide: “The index of refraction”; Practice Q1)
- I can state the two conditions needed for total internal reflection. (Guide: “Total internal reflection”; Practice Q4)
Calculation and skills
- I can use n = c/v to find a speed or an index of refraction. (Practice Q1, Q5c)
- I can apply Snell’s law with both angles measured from the normal, pairing each n with its own angle. (Guide: Worked example 1; Practice Q3)
- I can follow a ray through two or more parallel boundaries. (Guide: Figure 1; Practice Q5)
- I can calculate a critical angle from sin θc = n₂/n₁ and use it to decide whether a ray escapes. (Guide: Worked examples 1 and 3; Practice Q4, Q7)
- I can choose sin θ₁ and sin θ₂ as graph axes, plot data and find n from the slope of a best-fit line. (Guide: Worked example 2, Figure 3; Practice Q6c)
- I can describe a procedure for measuring angles of incidence and refraction, including a step that improves reliability. (Practice Q6a)
Reasoning
- I can predict whether a ray bends toward or away from the normal, without calculating, from the two indices. (Guide: “Snell’s law”; Practice Q2)
- I can explain why total internal reflection is impossible when light goes into a higher n. (Guide: “Total internal reflection”; Practice Q4)
- I can evaluate a claim about how a change of surrounding medium changes the critical angle and what is seen. (Guide: Worked example 3; Practice Q7c)
All ticked? Move on to Topic 13.4, Images Formed by Lenses, or return to the course roadmap.