Light questions This is a list of recently added questions about light. Play light quiz and see all the questions. What is the unit of measure of the luminous flux in the SI system?Lumen. The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the total quantity of visible light emitted by a source Created by: Tschuka hard 42% LuxLux170LumenLumen307CandelaCandela190IlluminanceIlluminance48physics riddles » Which of the following is the worst for eyesight during a sunny day?Wearing sunglasses without UV filter. Wearing sunglasses witout UV filter causes the pupils to dilate and eyes to absorb more UV rays than they normally would without the sunglasses. Hence, it's much better not to wear sunglasses at all, than to wear ones without UV filter.Created by: Ninjaihard 47% wearing sunglasses with UV filterwearing sunglasses with UV filter401wearing sunglasses without UV filterwearing sunglasses without UV filter4959not wearing sunglasses at allnot wearing sunglasses at all3772wearing sunglasses inside buildingswearing sunglasses inside buildings1334optics riddles » In what process sky colors (including blue sky and red sun) are created?Rayleigh scattering, named after the British physicist Lord Rayleigh (John William Strutt), is an elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation. Created by: Ninjaivery hard 33% iridescenceiridescence607Rayleigh scatteringRayleigh scattering1711miragemirage624atmospheric refractionatmospheric refraction2211optical illusions riddles » Which color has the greatest albedo?White. Albedo in Latin is simply "whiteness". It is the reflecting power of a surface - the ratio of reflected radiation from the surface to incident radiation upon it.Created by: Paweł Kołodziejczykhard 46% whitewhite3107blueblue1034redred1652blackblack848Latin riddles » What is "c" in E=mc^2?Speed of light. In words, energy equals mass multiplied by the speed of light squared.Created by: Paweł Kołodziejczykeasy 72% thermodynamic free energythermodynamic free energy870specific heat capacityspecific heat capacity1103speed of lightspeed of light6337Coulomb, unit of the electric chargeCoulomb, unit of the electric charge491discoverers riddles » What kind of building is that?Solar power plant. In The PS10 Solar Power Plant, 624 movable mirrors concentrate the sun's rays to the top of a 115 meter (377 ft) high, tower where a steam turbine is located. The plant is located near Seville, Spain.Created by: globalquiz.orgaverage 65% superlighthousesuperlighthouse2287solar power plantsolar power plant9580tent-type greenhousetent-type greenhouse1067a fountain in Dubaia fountain in Dubai1792electricity riddles » Which beverage is is fluorescent in UV light?Tonic water is transparent in daylight. Under ultraviolet light, the quinine makes it fluorescent (pictured), even though it is present in a negligible concentration.Created by: Luca Biaggihard 52% SpriteSprite3061milkmilk1815tonic watertonic water7149pineapple juicepineapple juice1715beverages riddles » The rainbow is violet on the inside of its arc. What color is it on the outside?Red. Visible light spans from red to violet. It is easy to remember, since wavelengths just outside the visible range are called infrared and ultraviolet.Created by: Hà Linh Chihard 55% blueblue3208greengreen1843yellowyellow3901redred11370colors riddles » Who should you expect to show stronger red-eye effect?Blue-eyed people. The iris plays no role in the effect, but the blue-eyed people have relatively low melanin in the fundus as well. Therefore, they show a much stronger red-eye effect, as the light passing fundus is not absorbed by melanin. The role of melanin in red-eye effect is nicely demonstrated in case of heterochromia (one eye blue, one brown): typically, only the blue eye displays the effect.Created by: Kantapat Rassameehard 54% blue-eyed peopleblue-eyed people4770brown-eyed peoplebrown-eyed people1426elderselders129there is no differencethere is no difference2451eyes riddles » What photographic technique was used to create this photo?Light painting. The photo was taken with long exposure. For the first 15 seconds, the author hold still with lights on, to achieve the light in background. Later, he switched off the light and wrote his name with light in his hand. He used his nose as a reference point so he could close the "O" letter - which explains the flare at this position.Created by: globalquiz.orgaverage 67% light paintinglight painting16643phototypographyphototypography2168overexposureoverexposure2473painting on the lenspainting on the lens3479photography riddles » Play physics quiz and see all the questions.