Graphite works as a semiconductor of electricity. In this project it as regulator or resistor.
Friends we use regulators in various electric appliances like fan, mixture etc. to increase or decrease it acceleration .Do you want to make regulator on your own? In this activity with the help of Graphite you are going to make a similar type of regulator. So lets start with the activity!
• As soon as metal rod touch's the graphite rod the fan starts working with speed.
• Then moving away the metal rod on graphiterod the acceleration (speed) of the fan decreasesgradually.
• Again moving metal towards the conducting wire the acceleration of fan increases.
As the metal rod touch's the graphite rod connected with the wire the circuit gets completed and current flows through the closed circuit .Thus the fan starts working. Now as when the metal rod is moved away from wire the acceleration of fan decreases because current through the fan decreases as graphite is semiconductor of electricity. Again when the metal rod is moved towards the wire the acceleration of the fan increases because current through the fan increases. This happens because moving away from wire the dist between metal rod and wire in creases and molecules of the graphite between them resists the current to pass through as graphite is semiconductor. Hence less amount of current pass and speed decrease and works as regulator to increase or decrease the speed . Thus graphite can work as resistor or regulator.
This mechanism is used in various electric appliances to regulate its speed or acceleration.
Questionnaire: 1. What is the pencil led made up of? (a) Carbon,
(c) Silicon 2. Which of the following is semiconductor of electricity? (a) Carbon,
(c) Silicon 3. Which other element then graphite is semiconductor of electricity? (a) Carbon,