2.20 Groupwork: to describe the usefulness of magnets in everyday  (Page 2/2)

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8. Fun with magnets

(a) Remove a paper clip from a glass full of water without getting your hands wet or emptying the glass.

(b) Try to move magnetic materials without touching them or letting your friends know how you manage it.

9. Something interesting

There are trains that work on the simple principle that opposing poles of magnets affect one another. A magnetic force draws arms below the train towards the tracks and thereby lifts the train so that it can float. Another magnetic field propels the train forwards. The train does not touch the track and there is therefore little friction to cause wear to the brakes or the track. Another example of such levitation (or floating) is that the train can achieve very high speeds.

10. Let’s test our knowledge. You may refer to your module to assist you with your answers.

(a) Complete: While two N poles will ____________________________ each other,

a N pole and a S pole will____________________________________. one another.

How will you determine whether a material is magnetic or non-magnetic?

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Which of the poles of a magnet is more powerful: the N pole or the S

pole? _______________________________________________________________

Complete: The direction of magnetic field lines around a magnet is from

the ____________________________ pole to the ________________________ pole

of the magnet.

Underline the characteristic that does not relate to magnets:

repelling, attracting, directional; expansion; polarity.

Underline the name(s) of the non-magnetic material(s): copper, steel, iron, cobalt, nickel.

True or false? Magnets can attract materials through other magnetic

materials. ____________________________________________________________

Picture one end of a bar magnet being held close to the N pole of the needle of a compass. What will the polarity of that end of the bar magnet be?

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Complete: If a steel knitting needle is stroked repeatedly with the south pole of a powerful magnet, the tip of the needle at which the stroking ends will

become a ________________________________________________________ pole

How can you determine whether a steel needle has been magnetised?

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Summative (10)

Assesment

Learning Outcome 2: The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

Assessment Standard 2.4: We know this when the learner application of knowledge: applies knowledge appropriately by connecting the learnt concept to a variation of the known situation.