A ray of light in air travels across a flat boundary into a block of transparent plastic. The angle of incidence is 54∘54^\circ54∘. The angle of refraction is 31∘31^\circ31∘.
Draw or describe a labelled diagram to illustrate this information.
Calculate the refractive index of the plastic.
A ray of light inside the plastic travels towards a flat boundary with air. The angle of incidence is 54∘54^\circ54∘. This ray does not emerge into the air. State and explain what happens to this ray.
216 exam-style questions on CIE IGCSE Physics 3.2 Light, covering 3.2.1a Reflection of light, 3.2.1b Images in a plane mirror, 3.2.2 Refraction of light, 3.2.2a Refraction of light, 3.2.2b Total internal reflection, 3.2.2c Refractive index and critical angle, 3.2.2d Optical fibres, 3.2.3a Converging and diverging lenses, 3.2.3b Ray diagrams and the nature of images, 3.2.3c Virtual images and the magnifying glass, 3.2.3d Correcting long-sightedness and short-sightedness, and 3.2.4 Dispersion of light. Each one has a worked solution and a mark scheme showing where the marks go.