--- title: Lenses and eyes — a lesson of Mova's school · trees and pragmatics description: «Lenses and eyes», a lesson of the physics course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: A lens is a piece of clear glass or plastic with curved sides that bends light on its way through; a lens thick in the middle gathers the light inwards. --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Physics](https://md.mova.elamur.ai/free/en/corpora/school/physics/) / Lenses and eyes # Lenses and eyes Lesson 22 of the physics course of Mova's primary school: 17 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/physics/22-lenses-and-eyes/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/0/) — A lens is a piece of clear glass or plastic with curved sides that bends light on its way through; a lens thick in the middle gathers the light inwards. - [1](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/1/) — Hold a magnifying glass over an ant and the bent light makes the ant look huge, but the same lens can gather sunlight into a tiny burning spot, so it is never pointed at the Sun or anything alive. - [2](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/2/) — Your eye has its own lens that makes a sharp, upside-down picture on the back of the eye, and your brain turns it the right way up. - [3](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/3/) — If an eye is a little too long or too short the picture lands in the wrong place, and glasses bend the light just enough to put it right. - [4](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/4/) — Telescopes and microscopes put lenses or mirrors together to show what our eyes alone cannot: craters on the Moon, or tiny creatures swimming in a drop of pond water. - [5](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/5/) — A magnifying glass is thicker in the middle and bends light inwards, making small things look bigger. - [6](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/6/) — A magnifying glass can focus sunlight into a hot spot that starts fires, so it is never pointed at the Sun or at anything living. - [7](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/7/) — The lens in your eye makes an upside-down picture on the back of the eye, and the brain turns it the right way up. - [8](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/8/) — The pupil, the dark hole in the middle of your eye, grows bigger in the dark and smaller in bright light. - [9](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/9/) — Glasses bend light a little so that it focuses properly in eyes that are slightly too long or too short; short-sighted people see near things well, long-sighted people see far things well. - [10](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/10/) — Looking straight at the Sun, even with sunglasses, can burn the back of the eye without any pain, and the damage can be permanent. - [11](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/11/) — An eclipse of the Sun is watched only with special eclipse glasses or a pinhole projector. - [13](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/13/) — A telescope gathers much more light than your eye and makes the picture bigger, and Galileo saw the moons of Jupiter with a small one in 1610. - [14](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/14/) — A microscope uses two lenses, each making the picture bigger again, and shows that a drop of pond water is full of tiny living things. - [15](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/15/) — A laser makes a narrow beam of light of one colour that hardly spreads, and it must never be shone into anyone's eyes or at planes. - [16](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/16/) — Light can travel along thin glass threads, called optical fibres, bouncing inside them, and the internet uses such fibres under the sea. - [17](https://md.mova.elamur.ai/free/en/corpora/school/physics/22-lenses-and-eyes/17/) — A mirage of water on a hot road is light from the sky bent by hot air near the road, which is why the puddle vanishes as you get closer. - ← previous: [Mirrors, rainbows and the blue sky](https://md.mova.elamur.ai/free/en/corpora/school/physics/21-mirrors-rainbows-and-the-blue-sky/) - next →: [Heat moves: hot to cold](https://md.mova.elamur.ai/free/en/corpora/school/physics/23-heat-moves-hot-to-cold/) - ↑ back to [Physics](https://md.mova.elamur.ai/free/en/corpora/school/physics/)