Conducts electricity

Electrical conductors and non-conductors

Investigation of solid substances for their electrical conductivity

Student experiment:

First, we examine various solid substances for their conductivity, e.g. metals, wood, coal, plastic, pencil lead.

All materials that we want to examine for electrical conductivity are placed in the open part of the circuit. When the light bulb lights up, they are conducting the electric current well.

Grade:

All substances that conduct electricity are called electrical conductors.
All substances that do not conduct electricity are called electrical insulators.

Examination of liquids for their electrical conductivity.

Student experiment:

Next, we examine various liquids for their conductivity. For example, we can use distilled water, vinegar, tap water, salt water, cooking oil.

Then we insert two electrodes into the vessel in which the liquid is located.

comment:
In those cases in which the incandescent lamp no longer shows any current flow, we can use a sensitive light-emitting diode.

Does the human body also conduct?

Student experiment:

Form a chain of students, use a battery and a sensitive measuring device to demonstrate the conductivity of the human body!

Summary:

The human body also conducts electricity. Therefore, be careful when handling electricity. A flashlight battery is not dangerous. But the electricity from the socket is life-threatening!
Good leaders:
All metals conduct electricity very well, especially platinum, gold, copper and aluminum, including coal.
Bad ladder:
Solutions of acids, bases and salts conduct electricity to a lesser extent. This also applies to tap water, damp earth and the human body.
Non-conductor:
Air, rubber, plastic, dry paper, oil, glass, ceramics and distilled water do not conduct electricity at all. These non-conductors are also called insulators.

What are electrons

Where does the electricity come from?
Is it already there in the wires?
Is it generated in the voltage source?
What is that what we call electricity and what flows through the line?

Student experiment:

A couple of students simulate the electrons that are powered by the voltage source. They demonstrate the voltage source = drive.
The rest of the class stands up, not too far apart, and stops. This is supposed to be the light bulb = inhibition.
The students who embody the electrons walk through the fixed group. There is some scramble and some friction.

Simple atomic model

All substances that we know are made up of small building blocks, the atoms. These atoms consist of a positively charged nucleus and the negatively charged electrons. You can imagine the structure of an atom in the same way as our solar system. In the solar system, all planets move around the sun. In the atom, all electrons move on certain shells around the atomic nucleus. The electrons on the outermost shell are only loosely connected to the atomic nucleus.

From the point of view of the atoms, all elements differ only in the number of electrons. The simplest atom is the hydrogen atom, it consists of the nucleus and an electron.

A copper atom also has an atomic nucleus, but a total of 28 electrons.

Electric current, a model

Similar to how water flows through a water pipe, electrons flow through a conductor (wire). Water flows in the water pipe, it is called a water flow.
Electrons flow in the electrical conductor, one speaks of an electrical current. In the water pipe, the water particles are set in motion by a pump. In the electrical conductor, the electrons are set in motion by the voltage source.

exercise:

What is the difference between a good, bad, and non-conductor?
Answer: mobility of electrons.How can one increase the drive of electricity?
Answer: By connecting two or more voltage sources in series.




Here you will find a Overview of further articles on the topic of electricity and heatit also contains links to tasks.

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