Page 157 - SCERT Kerala State Syllabus 8th Standard Basic Science Textbooks English Medium Part 1_Neat

Repeat the experiment using a steel nail instead of the soft iron
nail. Is the magnetism of the steel nail lost on stopping the supply
of current? Examine. Write down your findings in the science
diary.

On the basis of the experiments you have carried out, you might
have understood that permanent magnets of different shape and
strength can be made.

Significant learning outcomes

The learner can

explain with the help of experiments the fact that like poles
repel each other and unlike poles attract each other.
explain the directional property of a magnetic compass and
use it appropriately in required situations.

explain the magnetic properties of the earth with the
realisation that the earth behaves like a bar magnet.
explain magnetic field, magnetic lines of force, flux density,
magnetic induction, etc.
conduct different experiments related to magnets.

understand and explain differences in the magnetic
properties of soft iron and steel.

explain methods for increasing the strength of an
electromagnet.
explain methods to make permanent magnets of different
shapes artificially.

Let us assess

1. In the figure, AB is a bar magnet. CD is a soft
iron rod placed near the end B. Write down
which poles develop at the ends C and D .

156 Basic Science VIII