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My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited A question to think about… How can we make magnets? My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited The stroke method • Notice that the iron filings are not attracted to a magnetic object such as an iron nail. To make the iron nail into a magnet, you will need a strong bar magnet and a magnetic object. My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited The stroke method • First, stroke the iron nail about 20 times with one pole of a bar magnet. • Take note to stroke with the same pole. • Always repeat your strokes in the same direction. My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited The stroke method • Next, try to pick up the iron filings with the nail again. • The magnetised iron nail will be able to attract the iron filings. • The iron nail has now become a magnet. My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited The electrical method • If The We To the make can electromagnet iron also an nailmake can pick is only up magnets electromagnet, the a magnet sameusing things whenelectricity. coil itas is a anbar electric magnet, itmade has toatanow least battery 20or • connected Magnetswire this way times become a source around aofelectromagnet. electricity. a magnetic are called such an iron • object electromagnets. The iron nailas loses its nail. magnetism once it is • disconnected, Connect the ends andof will the not wireable be to atobattery. attract magnetic objects. My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited My Pals are Here! Science © 2008 Marshall Cavendish (Singapore) Private Limited