Which statement is correct?
The speed of light in a medium is equal to the speed of light in a vacuum multiplied by the refractive index of the medium.
The wavelength of light in a medium is equal to the wavelength of light in a vacuum divided by the refractive index of the medium.
Total internal reflection can occur when light travels from a medium of lower refractive index to a medium of higher refractive index.
The angle of refraction is proportional to the angle of incidence.
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.