DIY optical illusions
Awesome optical experiments with water and oil
- vegetable oil;
Place a coin in a cup so that it isn't in your line of sight. Just add water, and the coin will appear! Draw two horizontal arrows pointing in opposite directions. Place an empty glass in front of them. Fill the glass with water – the arrows change directions! You can achieve an equally amazing effect by drawing diagonal stripes or a chessboard. Wow! Optics is awesome!
Refraction is a phenomenon by which a wave, such as light, changes directions when transitioning from one medium to another. Different light-transmitting media have different optical densities, and therefore light travels through them at different speeds. The higher a medium’s optical density, the slower light travels through it. Refraction is everywhere, and we perceive it as completely normal: you can see how a straw in a glass of oil “breaks” at the border between the liquid and the air. Due to its shape, a glass of water acts as a lens capable of flipping an image. This creates stunning optical illusions. The refraction of light at the boundary of two media creates a paradoxical visual effect: objects overlapping both media appear "refracted upward" in the denser medium, while a ray of light entering a denser medium “refracts downward.” This effect causes bodies of water to seem shallower than they actually are. The refraction of light through glass or water is perhaps the simplest and most obvious example of beam distortion, but the laws of refraction apply to any waves – electromagnetic, acoustic, and even ocean waves.