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# How Strong Is Your Magnet?

### Introduction

Can your small magnet attract a paper clip from across the room? From across your desk? How can you find out how strong your magnet is? This experiment will help you find out!

You will need

• magnet
• spring clothespin
• scissors

Procedure

1. Work with a partner.
2. Clamp your magnet in the clothespin. Tape the clothespin to the bottom of the cup as shown in the sketch.
3. Pull out one end of a paper clip to form a hook. Touch the hook to the magnet. Does it stick?
4. Take turns with your partner and carefully add paper clips to the hook, one by one.
5. Count the total number of paper clips that you can hang onto the hook before the weight becomes too much for the magnet to hold and the paper clips fall. Write this number of paper clips on your data sheet on the line for zero pieces of tape.
6. Next, cut three squares of masking tape (1 X 1 inch; 2.5 X 2.5 cm). Stick the three pieces of masking tape on the bottom of your magnet. See the picture below. Now repeat your experiment and see how many paper clips you can hang on the hook. Make sure the hook touches the tape, not the magnet itself. Record your findings on your data sheet.