Energy is the capacity for doing work. The various forms of energy, interconvertible by suitable means, include potential, kinetic, electrical, heat, chemical, nuclear and radiant energy. Interconversion between these two forms of energy occurs only in the presence of matter. In the absence of matter energy can only exist in the form of radiant energy.
VII. Form sentences combining suitable parts of the sentences given in columns I and II.
1.The electric current is
1.the energy of position.
2.Kinetic energy is
2.electricity at rest.
3.Static electricity is
3. the flow of moving electrons.
4.Potential energy is
4.the energy of motion.
5.The direct current is
5.discharge of electricity.
6.the flow of electrons in one direction.
VIII. Discuss in the group.
1. Energy can be transformed from one form into another. Give an example.
The electric charge is also called electricity. We can generate electricity to illuminate our cities or we can store it in a battery to transport it. Electricity is a flow of electrons through a conductor. Copper is a good conductor so we use it in electric wires. PVC, on the other hand, is a good insulator and we use it to cover copper wires.
A simple electric circuit includes a battery with chemical paste, a carbon rod, a wire and a light bulb. The chemical paste contains an excess of electrons so when you connect the two poles of the battery, the copper wire attracts electrons. The electrons in the chemical paste repel the electrons in the carbon rod and make them flow through the ŮÓpper wire. When they arrive at the filament inside the bulb, they produce heat and emit light. That is we say that light is a photoelectric effect.
The nature of the electric charge is a mystery but we know interaction of the electric charges in space-time is responsible for the existence of nature.
III. Remember these words:
conductor, to store, to flow, wire, circuit, carbon, bulb, to include, rod.
IV. Translate the following words:
1. electric, electrical, electricity, to electrify, electrically, electrification, electrician;
2. conduction, conductor, conductivity, conductance, to conduct, conductive, non-conductor;
3. to magnetize, magnet, magnetically, magnetic, magnetization, to unmagnetize;
4. direct, to direct, direction, director, directly, directive, unidirectional.
V. Read the following information about electriciansí safety at work.
Electricians wear safety clothes like rubber shoes and gloves because accidents sometimes happen. Rubber is an insulator. Electrons canít go through it. Electricians usually turn off the electric power before working. They donít work outside when it is raining because water is a conductor. Electricians are not afraid of electricity but they respect its power.