--- title: Olympiad: machines at home and in the factory ★★★ — a lesson of Mova's school · trees and pragmatics description: «Olympiad: machines at home and in the factory ★★★», a lesson of the technology course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: This olympiad lesson mixes the machines of the whole course, from the factory floor to the kitchen, the bike shed and --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/) [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/) / [Technology](https://md.mova.elamur.ai/free/en/corpora/school/technology/) / Olympiad: machines at home and in the… # Olympiad: machines at home and in the factory ★★★ Lesson 42 of the technology course of Mova's primary school: 15 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/technology/42-olympiad-machines-at-home-and-in-the-factory/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/0/) — This olympiad lesson mixes the machines of the whole course, from the factory floor to the kitchen, the bike shed and the lift, into puzzles where you must think in two or three steps. - [1](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/1/) — Most puzzles hide a trap: a machine that seems to make cold really only moves heat, a magnet that pushes away a metal it cannot pick up, a child who is old enough but not tall enough. - [2](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/2/) — Picture a puzzle card at a science club: «A chain wheel has 40 teeth and the back cog 20. - [3](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/3/) — How far does the back wheel turn when you pedal once?» Count teeth, not guesses: 40 teeth pass, the cog turns twice, and so does the wheel. - [4](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/4/) — People talk big and small too: «I've told you a million times» means many times, and «it's nothing, it's just a bit warm» about a swelling battery is a real danger played down. - [5](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/5/) — Read every word, find the one fact that cracks the puzzle, and check the answer against what really happens. - [6](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/6/) — On a bike, the back wheel turns as many times for each turn of the pedals as the back cog's teeth fit into the chain wheel's teeth: a 40-tooth chain wheel with a 20-tooth back cog turns the back wheel twice for every pedal turn. - [7](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/7/) — A bigger back cog makes pedalling easier but slower, good for hills; a smaller back cog makes it harder but faster. - [8](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/8/) — A fridge, an air conditioner and a heat pump do not make cold or heat from nothing: they move heat from one place to another, and a fridge lets the heat out from the pipes at its back. - [9](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/9/) — In a sorting plant, magnets pull out steel, a spinning magnet pushes aluminium cans off the belt even though aluminium is not magnetic, and air jets with cameras pick out the plastics. - [10](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/10/) — Freezing stops most germs growing but does not kill them; water gets bigger when it freezes, which is why a full glass bottle can crack in the freezer. - [12](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/12/) — Birds can sit on a power line because they touch only one wire and not the ground; a kite string touching a line can let electricity pass through a person to the ground. - [13](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/13/) — In the UK children use a child seat or booster until they are 12 years old or 135 cm tall, whichever comes first. - [16](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/16/) — A crumple zone at the front and back of a car is built to squash in a crash so the people inside are slowed more gently. - [17](https://md.mova.elamur.ai/free/en/corpora/school/technology/42-olympiad-machines-at-home-and-in-the-factory/17/) — A bicycle has 2 wheels, a tricycle 3, a car 4, and a usual train carriage 8. - ← previous: [Rivers, canals and boats: locks, weirs, water-mills, barges and how not to tip a rowing boat](https://md.mova.elamur.ai/free/en/corpora/school/technology/41-rivers-canals-and-boats-locks-weirs-water-mills-barges-and-how-not-to-tip-a-rowing-boat/) - next →: [Olympiad: transport, building and energy ★★★](https://md.mova.elamur.ai/free/en/corpora/school/technology/43-olympiad-transport-building-and-energy/) - ↑ back to [Technology](https://md.mova.elamur.ai/free/en/corpora/school/technology/)