# 3 ways to determine the polarity of a magnet

Chances are you've ever heard the following phrase: "Opposites attract." While this cliché may not be the best advice when it comes to relationships, it is the general rule of thumb for determining the polarity of a magnet. Because humans inhabit a gigantic magnet (which is planet Earth), understanding the polarity of a small-scale magnet will help you understand the larger magnetic field that protects us from space radiation. If you want to label your magnets for future use or just want to do a fun science experiment, here are some easy methods to determine the polarity of your magnets.

## Steps

### Method 1 of 3: Use a Compass

#### Step 1. Gather your supplies

You only need a compass and a magnet. You can use any type of compass, but the simplest type of magnet for this method should be a ring or bar magnet.

#### Step 2. Test the compass

On a normal compass, the needle that points north is usually the red one. However, it is better that you always check this detail. If you know where north is located geographically from your current location, you can easily see the end of the compass needle pointing in that direction.

• If you are not sure where geographic north is located, you can go out at noon (when the sun is highest in the sky) to determine the north end of the needle. You should hold the compass flat in your hand with the southern end closest to your body.
• Observe the position of the compass needle. If you live north of Earth's equator, the north end of the needle should point toward you and the south end toward the sun. If you live south of the Earth's equator, the south end of the needle should point toward you.

#### Step 3. Place the compass on a flat surface (like a table)

Make sure the surface is free of magnetic or metallic materials that can cause an erroneous reading. Even certain objects (such as key chains or knives) can interfere with the experiment. You will notice that the north end of the needle points to your geographic north.

#### Step 4. Place the magnet on the table

If you are using a ring magnet, the north and south poles should be on the two flat surfaces. If you are using a bar magnet, the poles should meet on both ends.

#### Step 5. Place the magnet next to the compass

If you are going to use the ring magnet, you have to place it on its side and hold it with your index finger so that one of the flat sides points towards the compass.

### If you are using a bar magnet, you should place it perpendicular to the compass so that one end of the magnet is close to the compass

#### Step 6. Look at the compass needle

Because the needle is a small magnet, the south end will be attracted to the north pole of the magnet.

### Method 2 of 3: Create a Compass with a Bar Magnet

#### Step 1. Find a piece of string

You can use any type of string that you find around your house (for example, a piece of yarn or a ribbon for wrapping gifts). The string should be long enough to wrap around the magnet and suspend it.

### A rope of approximately one meter is considered adequate for most cases. You can calculate this measurement by holding the string with both hands. With your right hand, hold the string over your nose. Then extend your left arm as far as you can. The length of the rope between the left and the right hand is almost one meter

#### Step 2. Tie the string tightly around the bar magnet

You must make sure that the rope is well tied so that the magnet does not slip through the knot. Note that this method is not the most appropriate if you have a ring magnet or a magnetic sphere.

#### Step 3. Keep the rope away from your body

Make sure the magnet can rotate freely without coming into contact with any impediment. As soon as it stops rotating, the end pointing north will be the north pole of the magnet. Congratulations! You just created a compass.

### Method 3 of 3: Float a Magnet

#### Step 1. Gather your supplies

This method requires some basic household products that you probably have on hand. If you have a small magnet, a piece of Styrofoam, water, and a container, you can develop a fun experiment that will help you determine the polarity of your magnets.

#### Step 2. Fill a cup, bowl, or small plate with water

You don't need to fill the container completely, just enough so that the Styrofoam can float freely.

#### Step 3. Prepare the Styrofoam

This product should be small enough to reach into the container, but not so small that it can hold the magnet. If you have a very large piece of styrofoam, you can cut it a little so that it fits into the container.

#### Step 4. Place the magnet on the styrofoam

The styrofoam pad should rotate until the north pole of the magnet points north.