Page 3 - CBW Magnet & their effects

Earth also acts like a giant magnet. That is why compasses work reliably and always
point in the same direction.

a) Why does a freely suspended magnet align itself in the north-south direction?
b) How do sailors use magnets in navigation?
c) What feature of the Earth allows a compass to function?
d) Name the parts of a magnet where the magnetic field is strongest.

11. Magnetic Interaction Rule:
When two magnets are brought close to each other, like poles (North-North or South-
South) repel, and unlike poles (North-South) attract. This property is called magnetic
interaction. It is useful for identifying the poles of a magnet. For example, if the north
pole of a known magnet repels one end of an unknown magnet, that end must also be a
north pole.

a) State the rule of magnetic interaction.
b) How can this rule help identify unknown poles of a magnet?
c) What happens when the north pole of a magnet is brought close to another north
pole?
d) What conclusion can be drawn if two magnets attract each other?

12. Magnetic vs Non-Magnetic Materials:
Refer to the given table.

a) From the data, name two elements that show similar magnetic behavior.
b) From the table, can we say that all metals are magnetic? Justify your answer.
c) If a student tests a rubber band with a magnet, what will be the expected result?
d) What common property do iron, nickel, cobalt, and steel share in the table?

13. Testing an Unknown Magnet:
A student places a bar magnet near another unknown bar. The unknown bar is attracted
to the magnet. Then, the student reverses the poles of the known magnet and observes
attraction again. Attraction alone cannot confirm whether the unknown bar is a magnet
or an iron bar.

a) Why is attraction not a conclusive test to confirm that an object is a magnet?
b) What observation would confirm that the unknown bar is a magnet?