Light travels in a vacuum and then enters a transparent plastic block. The speed of light in the plastic block is 1.5 × 108 m/s.
Which statement about the speed of light is correct?
The speed in a vacuum is 2.02.02.0 times the speed in the plastic.
The speed in the plastic is 2.02.02.0 times the speed in a vacuum.
The speed in the plastic is the same as the speed in a vacuum.
The speed in a vacuum is 1.5×1081.5 \times 10^81.5×108 times the speed in the plastic.
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.