Real, inverted, magnified. Section E: Optical Instruments (Aktiviti 13.5 – Periscope) Question: Draw a labelled diagram of a periscope using two prisms. Explain how total internal reflection helps in image formation.
The average refractive index of glass, n = (1.52 + 1.53 + 1.52 + 1.49) / 4 = 1.515 Thus, the refractive index of the glass block is 1.52 . Section B: Calculation Problems (Aktiviti 13.2) Question 1: The speed of light in a medium is 2.0 × 10⁸ m/s. Calculate the refractive index of the medium. (Speed of light in vacuum = 3.0 × 10⁸ m/s) Real, inverted, magnified
A light ray travels from water (n = 1.33) into air. The angle of incidence in water is 35°. Calculate the angle of refraction in air. The average refractive index of glass, n = (1
Using Snell’s Law: n₁ sin i = n₂ sin r 1.33 × sin 35° = 1.00 × sin r 1.33 × 0.574 = sin r sin r = 0.763 r = sin⁻¹ (0.763) = 49.8° Section C: Total Internal Reflection (Aktiviti 13.3) Question: The critical angle for diamond is 24.4°. Calculate the refractive index of diamond. (Speed of light in vacuum = 3
n = speed of light in vacuum / speed of light in medium n = (3.0 × 10⁸) / (2.0 × 10⁸) = 1.5
Why does a diamond sparkle more than a glass piece?