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Our Surroundings 



Polarity. The polarity of a magnet is its tendency to point 

 north and south when suspended. The end which points north 

 is called the north pole of the magnet and the end which points 

 to the south is called its south pole. Near the poles of a 

 magnet the attractive power is much stronger than near the 



middle. 



Experiments with a 

 Magnet. Scatter iron filings 

 over a bar magnet. Notice 

 that they collect for the most 

 part in two clusters, one near 

 each end, or pole, of the mag- 

 net. Few, if any, collect at 

 the middle. 



To show polarity, suspend 

 by a silk thread a piece of 

 magnetized steel about eight 

 inches long, so that it balances. 

 When it comes to rest, notice 

 what position it assumes with 

 reference to the points of the 

 compass. Whirl it several 

 times, and after each whirl let 

 it come to rest without in- 

 terference on your part. 

 Notice whether it tends to 

 take the same position each 

 time. 



In the same way, find out 

 the poles of a second similar 

 piece of magnetized steel. 

 Bring the north (N) pole of 

 the first magnet near the N 

 pole of the second magnet and 

 observe what occurs. Test the 



attraction Q f the south (S) 



Poles for each other. Then 



