Page 60 - Science Class 06

Some of the objects will get a racted by A non-conductor of electricity is called an
the magnet while others shall remain
unaffected. So, materials can be either
magne c (sensi ve to magne c force) or
non-magne c (indifferent to this force).
Conduc on of Electricity
We use electricity at very steps in day-to-
day life—for light, for heat and for running
various home appliances. These appliances
include electric press, washing machine,
electric shaver, refrigerator, television-set,
etc. We know that when the concerned
switch is on, the current of electricity flows
from the source up to the appliance.
The covering of wire is made
of plas c or rubber.
In case of an electric bulb, it reaches the
filament inside the bulb and heats it. The
filament gets white hot to emit light all
around.
The electric current flows through a cable
that has two or three wires inside it—a
black, a red and a green–generally. Inside
each of these black, red and green covers,
there are fine thread wires of copper that
carry the electric current. Copper and other
metals are good conductors of electricity.
But the covers made of rubber or plas cs
which are non-conductors of electricity.
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insulator also. Remember that 100% pure
water and air are bad conductors of
electricity. But normal water has various
salts dissolved in it. These salts conduct
electric current.
It is clear that materials can be good
conductors, bad conductors or non-
conductors (insulators) of electricity. It is
always safe to wear rubber-soled shoes,
chappals, etc. and keep the hand quite dry
while handling electric appliances.
1. Name any three substances which are
soluble in water.
2. What is the difference between
malleability and duc lity?
3. Why do gases diffuse faster than
liquids?
4. Why do woollen clothes keep us warm?
5. What are insulators?
6. Give examples of five insulators.
Electricity is produced in a power-sta on
and from there, it is transmi ed to towns
and further to homes through wires
supported by high pylons and poles.
Transformers are also used to step up and
step down the current-carrying wires.
Science-6