--- title: "Magnetic Fields" description: "Describe magnetic poles (north and south), explain attraction and repulsion between poles, describe magnetic field lines plotted using a compass, and explain the Earth's magnetic field and its practic" canonical: https://lightmysky.com/learn/science/magnetic-fields-mt_56aspHjU19 source: https://lightmysky.com/learn/science/magnetic-fields-mt_56aspHjU19.md retrieved: 2026-10-19 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Magnetic Fields Describe magnetic poles (north and south), explain attraction and repulsion between poles, describe magnetic field lines plotted using a compass, and explain the Earth's magnetic field and its practical uses Subject: Science · Area: Forces & Motion · Ages 11 to 12 Page: https://lightmysky.com/learn/science/magnetic-fields-mt_56aspHjU19 ## Ready when they can - States the rule for attraction and repulsion of magnetic poles - Draws the magnetic field pattern around a bar magnet from memory or compass readings - Explains why a compass needle points north - Explains that the Earth has a magnetic field and describes how it is used for navigation ## Lesson: Magnetic Fields You already know that magnets have a north pole and a south pole, and that like poles push apart while unlike poles pull together. That pushing and pulling happens because every magnet is surrounded by an invisible area called a magnetic field. Field lines show the shape of this invisible area. Each line leaves the north pole, loops around the magnet, and goes back in at the south pole. You can see this pattern for real by moving a small compass around a bar magnet and marking which way the needle points at each spot. *(drawing: Follow one field line: it leaves the north pole, loops around the magnet, and goes back in at the south pole.)* **Example.** Mia moves a compass step by step around a bar magnet. Close to the poles, the needle swings quickly and the lines she draws are packed tightly together. Further away, the needle turns more slowly and her lines spread out. This tells her the field is strongest near the poles. **Tip.** The Earth behaves like a giant bar magnet buried inside it. That is why a compass needle always swings around and settles pointing roughly north: it is lining up with the Earth's own magnetic field, just like it lines up near a bar magnet. A compass works because its needle is a tiny magnet that can swing freely. It lines up with any magnetic field it sits in, whether that field comes from a bar magnet or from the Earth itself. One more rule helps you read a field map: field lines never cross each other. At every spot the field points in just one direction, so two lines can never meet. **Recap.** A magnet's field lines run from its north pole to its south pole, and Earth's own magnetic field is what makes every compass point north. ## Practice 28 questions on this page, each with its working shown. ## Needs first - [Magnetic Poles](https://lightmysky.com/learn/science/magnetic-poles-mt_jgNB2752b9) ## Opens up - [Electromagnets](https://lightmysky.com/learn/science/electromagnets-mt_2qkn8Lhc8e)