Describe an activity to show that the 'lead' of a pencil conducts elec...
We will sharp a small pencil at both ends, and connect the two naked ends of the ‘lead’ to the circuit. ‘lead’ of the pencil conducts electricity. The lead of a pencil is made of a mixture of clay and graphite, and graphite(a form of carbon) is a good conductor of electricity.
The above activity shows that the lead of the pencil conduct electricity but if in the place of lead, we put slphur which is a nonmetals will not make the bulb to glow. This shows that piece of sulphur does not conduct electricity.
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Describe an activity to show that the 'lead' of a pencil conducts elec...
Conduct high voltage electrical current to 1 and and keep ur finger on other end
if u get shocked
it is a conductor
note I am not responsible if something happens
Describe an activity to show that the 'lead' of a pencil conducts elec...
Introduction:
In order to demonstrate that the 'lead' of a pencil conducts electricity while a piece of sulphur does not, we can perform a simple experiment that involves the use of a circuit and testing the conductivity of both materials. This experiment will help us understand the differing electrical properties of these two substances.
Materials:
- Pencil with graphite 'lead'
- Piece of sulphur
- Battery
- LED bulb
- Connecting wires
- Crocodile clips
- Circuit board
Procedure:
1. Connect the circuit: Begin by setting up a simple circuit using the circuit board, battery, LED bulb, and connecting wires.
2. Attach the pencil lead: Take one end of a connecting wire and attach it to the positive terminal of the battery. Securely attach the other end of the wire to a crocodile clip.
3. Connect the pencil lead to the circuit: Take another connecting wire and attach one end to the crocodile clip connected to the positive terminal. Attach the other end of the wire to one of the terminals on the circuit board.
4. Insert the pencil lead into the circuit: Take the pencil with the graphite lead and insert it into the terminal on the circuit board, ensuring it is securely connected.
5. Observe the LED bulb: Turn on the circuit and observe whether the LED bulb lights up. If the bulb lights up, it indicates that the pencil lead is conducting electricity.
Explanation:
1. Conductivity of pencil lead: The 'lead' of a pencil is made of graphite, which consists of carbon atoms arranged in a layered structure. These layers allow the free movement of electrons, making graphite a good conductor of electricity. When the circuit is completed by connecting the pencil lead to the battery, the flow of electrons can occur, causing the LED bulb to light up.
2. Non-conductivity of sulphur: On the other hand, sulphur is an insulator and does not conduct electricity. It does not have free-moving electrons like graphite, which inhibits the flow of electric current. Therefore, when a piece of sulphur is inserted into the circuit, the electrons cannot pass through it, resulting in the LED bulb not lighting up.
Conclusion:
By performing this simple experiment, we can clearly observe the difference in electrical conductivity between the 'lead' of a pencil (graphite) and a piece of sulphur. The graphite allows the flow of electrons and conducts electricity, while sulphur acts as an insulator and does not allow the passage of electric current. This experiment highlights the importance of understanding the electrical properties of different materials and their applications in various fields.
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