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Magnets PowerPoint Presentation

Magnets

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Magnets

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Presentation Transcript

  1. Magnets

  2. Two Poles

  3. What is a magnet? • A magnet is an object that attracts certain materials usually objects made of iron or steel.

  4. A magnet has two ends called magnetic poles or just poles for short. • A magnet’s pull is strongest at the poles.

  5. Poles are usually marked North andSouth. • What is each end of a magnet called?

  6. Magnetic Forces

  7. Forces you feel when playing with magnets can be pushes or pulls.

  8. A magnetic field is the space all around a magnet where the force of the magnet can act. • You can’t see the field.

  9. Forces between magnetic poles are like forces between electric charges. • Opposite magnetic poles attract, and like poles repel. North and South poles attract. • North and North poles repel or push away. • South andSouth poles repel or push away.

  10. Where is the pull of a magnet strongest?

  11. Compass

  12. The North and South seeking poles of magnets have been helpful to people for hundreds of years.

  13. People have used magnets to find direction.

  14. The first magnets used were made of heavy natural material called a lodestone, which is a mineral magnetite. • A compass today uses a lightweight magnetic needle that is free to turn. • A compass needle points along an imaginary line connecting the North and South poles. This is because earth is like a giant magnet.

  15. Field lines of earth’s magnetic field come together close to the planet’s North and South poles.

  16. How does a compass work?

  17. The north-seeking pole of the free-moving magnet in the compass points to Earth’s North Pole.

  18. Summary

  19. Magnets are objects that attract materials such as iron. • Every magnet has two magnetic poles. • Magnetic forces are caused by the interaction of magnetic fields. • Earth’s magnetic field is like the field of a bar magnet. • A compass needle interacts with earth’s magnetic field.

  20. Review

  21. How can you find the poles of a magnet?

  22. Find out where the magnet’s pull is strongest.

  23. What is a magnetic field?

  24. The place where magnetic forces act.

  25. Which type of magnet has a field that is about the same shape as the magnetic field of the earth?

  26. A bar magnet

  27. How many poles does a magnet have?

  28. Two

  29. The End • Thank You any questions? • By: Rachel Tanner