Magnets: Attract and Repel - First Grade Science
Have you ever used a colorful alphabet magnet to stick a drawing to your kitchen refrigerator door, or played with magnetic building tiles that snap together with a satisfying click? Magnets seem almost magical because they can push and pull objects without ever touching them! Magnetism is an invisible physical force produced by moving electrical charges inside certain metals. By exploring how magnets work, which materials they attract, and how magnetic poles interact, you uncover one of the most useful and exciting forces in science.
What is a Magnet?
A magnet is a piece of metal, rock, or ceramic that produces an invisible area of magnetic force around itself called a magnetic field.
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| WHAT MAGNETS ATTRACT |
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| MAGNETIC METALS (Magnets Attract!) NON-MAGNETIC (Magnets Ignore!) |
| - Iron and Steel (Paperclips, nails)- Wood (Pencils, wooden blocks) |
| - Nickel (Certain coins and metals) - Plastic (Legos, toy cups) |
| - Cobalt (Industrial alloys) - Glass (Marbles, windows) |
| - Aluminum (Soda cans, foil) |
| - Paper, rubber, cloth, leather |
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Not All Metals Are Magnetic!
A common misconception is that magnets stick to all metals. This is false! Magnets only stick to specific metals, primarily iron, nickel, cobalt, and steel (which is made from iron). If you touch a magnet to an aluminum soda can, a copper penny, or a gold ring, nothing happens: they are completely non-magnetic!
The Two Poles of a Magnet
Every single magnet, no matter its shape or size, has two distinct ends called magnetic poles: a North Pole (N) and a South Pole (S). The magnetic force is concentrated most powerfully at these two poles.
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| A BAR MAGNET |
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| +-----------------------+-----------------------+ |
| | NORTH POLE | SOUTH POLE | |
| | [N] | [S] | |
| +-----------------------+-----------------------+ |
| Red (North) Blue (South) |
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The Golden Rule of Magnetism: Attract and Repel
When you bring two magnets near each other, their poles interact in a predictable, fascinating way according to the fundamental law of magnetism.
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| THE LAW OF MAGNETIC POLES |
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| OPPOSITE POLES ATTRACT! (Pull Together) |
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| [ NORTH (N) ] =====> PULL TOGETHER <===== [ SOUTH (S) ] |
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| North and South pull toward each other with a strong snap! |
| ----------------------------------------------------------------- |
| LIKE POLES REPEL! (Push Away) |
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| [ NORTH (N) ] <===== PUSH AWAY =====> [ NORTH (N) ] |
| [ SOUTH (S) ] <===== PUSH AWAY =====> [ SOUTH (S) ] |
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| Two North poles (or two South poles) violently resist and push away!|
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Attract: The Magnetic Snap
The word attract means to pull toward. When you bring a North pole close to a South pole, the invisible lines of magnetic force loop together, pulling the two magnets toward each other until they snap tight.
Repel: The Invisible Wall
The word repel means to push away. If you try to push two North poles together (or two South poles together), you will feel a strange, squishy invisible resistance, like an invisible rubber cushion pushing your hands apart! No matter how hard you push, the like poles resist meeting.
The Magnetic Field
Surrounding every magnet is an invisible zone of force called a magnetic field. You cannot see the field with your eyes, but you can reveal it using fine iron filings!
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| REVEALING THE MAGNETIC FIELD |
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| . - ~ ~ ~ - . . - ~ ~ ~ - . |
| . ' ' .' ' . |
| / +-----------+ +-----------+ \ |
| | | NORTH (N) | ===> | SOUTH (S) | | |
| \ +-----------+ +-----------+ / |
| . ' ' .' ' . |
| ' - _ _ _ - ' ' - _ _ _ - ' |
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| Iron powder sprinkles align along curved lines of magnetic force |
| traveling from the North pole to the South pole! |
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Earth is a Giant Magnet: The Compass
Did you know that the planet Earth itself is a gigantic magnet? Deep inside Earth's core, swirling liquid molten iron generates a massive planetary magnetic field with magnetic North and South poles. A magnetic compass contains a lightweight magnetized needle balanced on a sharp pin. Because opposite poles attract, the North end of the compass needle always swings around to point directly toward Earth's magnetic North Pole, helping hikers, sailors, and pilots navigate anywhere in the world!
Chapter Review Exercises
Question 1: What is a magnet, and what is the invisible area of force that surrounds it called?
Question 2: Name two metals that a magnet will attract, and two metals that a magnet will NOT attract.
Question 3: State the Golden Rule of Magnetism regarding how opposite poles and like poles behave.
Question 4: How does a hiking compass use Earth's magnetic field to help travelers find their way?
Solutions and Explanations
Solution 1: A magnet is an object that produces magnetic force capable of attracting iron and steel. The invisible area of force surrounding a magnet is called a magnetic field.
Solution 2: A magnet will attract iron and steel (or nickel and cobalt). A magnet will not attract aluminum and copper (or gold and silver).
Solution 3: The Golden Rule of Magnetism is: Opposite poles attract (North attracts South), and like poles repel (North pushes away North, and South pushes away South).
Solution 4: Earth acts like a colossal magnet with its own magnetic poles. A compass contains a magnetized needle that pivots freely; the North pole of the needle is attracted toward Earth's magnetic North, providing a reliable reference for navigation.