Light, Reflection & Electromagnetic Radiation is one of 9 topics in the Grade 12 Technical Sciences CAPS syllabus, covered across 3 lessons on Study Vault. Below are real practice questions from this topic with full worked answers.
Sample practice questions
Easy
1. According to the law of reflection, how does the angle of incidence compare to the angle of reflection?
They are equal, both measured from the normal
The angle of reflection is always double the angle of incidence
The angle of reflection is always 90 degrees
They are unrelated to each other
Answer: They are equal, both measured from the normal — The law of reflection states the angle of incidence equals the angle of reflection, both measured from the normal.
Easy
2. Which formula correctly defines the refractive index n of a medium?
n = c/v
n = v/c
n = c x v
n = c + v
Answer: n = c/v — Refractive index is defined as n = c/v, the ratio of the speed of light in a vacuum to the speed of light in that medium.
Medium
3. Name the law that relates the angles and refractive indices at a boundary between two media: n1 sin(theta1) = n2 sin(theta2).
Answer: Snell's Law — Snell's Law states n1 sin(theta1) = n2 sin(theta2), relating angles and refractive indices at a boundary between two media.
