Conductors and Insulators
Will electric current pass throw all materials?
If an electric wire is cut, we could see a metal wire surrounded by another material. Do you know why it is so?
The rate of flow of electric charges in a circuit is called electric current. The materials which allow electric charges to pass through them are called conductors. Examples: Copper, iron, aluminum, impure water, earth etc.,
The materials which do not allow electric charges to pass through them are called insulators or non-conductors.
Examples: plastic, glass, wood, rubber, china clay, ebonite etc.,
Activity 4: Connect the objects given in the table between A and B and write whether the bulb glows or not.
Safety measures to safeguard a person from electric shock
I. Switch off the power supply.
II. Remove the connection from the switch.
III. Push him away using non - conducing materials.
IV. Give him first aid and take him to the nearest health centre.
More to Know
Thomas Alva Edison (February 11, 1847 October 18, 1931) was an American inventor. He invented more than 1000 useful inventions and most of them are electrical appliances used in homes. He is remembered for the invention of electric bulb.
Produce electricity using copper plates, zinc plate, connecting wires, key, beaker and porridge (rice water) [the older the porridge the better will be the current]
Arrange copper and zinc plates in series as shown in the figure. Half fill two beakers with porridge. Connect the copper plate with the positive of and LED bulb and zinc to the negative. Observe what happens.
Now you can replace porridge with curd, potato, lemon etc.