The double convex lens/mirror is symmetrical across both its horizontal and vertical axis. Each of the lens's two faces can be thought of as originally being part of a sphere. The fact that a double ...

Save guides, add subjects and pick up where you left off with your BBC account. Light is refracted when it enters a material like water or glass. Depending on the density of the material, light will ...

The questions in this quiz are suitable for GCSE physics students studying convex and concave lenses, real and virtual images, magnification and colour. If you struggled with the quiz, don't panic - ...

Light travels at different speeds based on the medium it passes through. For example, in a vacuum, it travels at 3.0 × 10^8 m/s in a straight line. But when directed towards glass, air, diamond, water ...

Adaptive liquid lens: A lens based on a new electrically responsive fluid changes shape, and thus focal length, when a voltage is applied. (Courtesy: Miao Xu, Hefei University of Technology) Materials ...