Familiar Types of Circuits

Exercise 2. (Translate the text into native language)

Exercise 1. (Read the text)

Find the correct variant. Remember it.

The main information about electric circuit

Тема 10-11. Электрическая цепь.

Retell the main information from the Text.

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"Electrical circuit"

Give the Ukrainian equivalents:

Circuit, resistor, voltage source, conductor, consist of, reduce, supply, connect, compare, difference, pass through, no (current), a short, an open, trouble, result in, from.

Read the Text:

This is a circuit. Its elements are a voltage source, a resistor and a con­ductor. The circuit consists of a volt­age source, a resistor and a conductor. A. voltage source supplies current. A resistor reduces current. A conductor connects the elements of the circuit.

Compare circuit "a" with circuit "b". What is the difference between them? Current passes through circuit "a" while no current passes through circuit "b". Circuit "b" has an open. No current through circuit "b" result's' from an open. An open and a short are troubles in a circuit. A trouble in a circuit may result in no current in it.

Translate the Text:

1) circuit "a" consists of…

a) resistors and conductors;

b) a voltage source and resistors;

c) a voltage source, a resistor and a conductor.

2) a voltage source…

a) conducts current;

b) reduces current;

c) supplies current.

3) a conductor…

a) connects the elements;

b) connects of laws;

c) connects of resistors.

Since you cannot see the electricity flow in circuits, you must "reason" where the current flows. To help you in such reasoning, make drawings or plans first. Then if it appears to work "on paper", do the wiring.

Any circuit is provided with a voltage source, a conductor, and a switch. A voltage source supplies current. A conductor is used for connecting the elements of the circuit. A switch is used for control­ling the current in the circuit.

There are many kinds of circuits, such as open circuits, closed circuits, short circuits, parallel circuits, and series circuits.

The circuit is said to be open when a switch is at rest or not being pressed or closed. A broken wire is an example of open cir­cuits. An open circuit results in no current in it.

A closed circuit is simply a complete circuit. Pressing a pushbut­ton or making proper connections refers to closing circuits.

Short circuits are seldom desirable. They often result in damage. In other words, damage in the circuit often results- from the short circuit. The short circuit refers to the conditions in the circuit which are the cause of fires, "blown" fuses, etc. Fuses are used as safety devices to stop the flow if it should become too great.

In everyday electric work, we very often -deal with circuits where the current is divided between two or more branches. When a circuit is divided in such a manner that part of the current goes through one branch and part through another, it is called a parallel circuit. A parallel circuit has the main line and parallel branches. In parallel circuits there is a difference between an open in the main line and an open in a branch. An open in the main line of a circuit of this type results in no current in the whole circuit while an open in a parallel branch results in no current in that branch only. This is the advantage of a parallel circuit.

When electrical devices are in a line so that the current is not divided at any point, they are said to be in series. The electric bell circuit is considered to be a typical example of a series circuit. The - (minus) terminal of each part of the circuit is joined to the + (plus) terminal of the next part, so that all the current does flow through each part of the circuit.

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