Editing Compression (physics) (section)

=== Internal combustion engines ===
In [[internal combustion engine]]s the explosive mixture gets compressed before it is ignited; the compression improves the efficiency of the engine. In the [[Otto cycle]], for instance, the second stroke of the piston effects the compression of the charge which has been drawn into the cylinder by the first forward stroke.<ref>{{Cite book |last=Heywood |first=John |url=https://books.google.com/books?id=OmJUDwAAQBAJ |title=Internal Combustion Engine Fundamentals 2E |date=2018-05-01 |publisher=McGraw Hill Professional |isbn=978-1-260-11611-3 |language=en}}</ref>