1. 2 nd ESO - TECHNOLOGY DEPARTMENT

2. WE USE CIRCUITS… At Home In Cities In Industry

3. TYPES OF CIRCUITS ELECTRICAL CIRCUITS Elements move using electricity as energy power. PNEUMATIC CIRCUITS Elements move using compressed air stored in a deposit. HYDRAULIC CIRCUITS Elements use oil under pressure from a pump.

4. ELECTRICAL CIRCUITS  Electricity travels around a path. This path is an electrical circuit. There is a source of electricity, and a continuous path from one side of the source to the other side. In the image below, the source is a battery.  An electrical circuit is a set of connected elements that allow the circulation of an electrical current. Electricity travels from one battery point, through the light and the switch (which is “connected”, or “closed”), and returns to the other battery point. This path forms a complete circuit.

5. CIRCUIT ELEMENTS  There are five types of basic elements: GENERATOR RECEIVER CONDUCTORS CONTROL ELEMENT PROTECTION ELEMENT ELEMENT

6. THE GENERATOR: Produces and moves electrical energy through the circuit. Eg. batteries, alternators, dynamos, etc. RECEIVERS: Receive electrical energy and transform it into other types of energy; light, sound, heat… Eg. bulbs, motors, speakers, etc. CIRCUIT ELEMENTS

7. CONDUCTORS: connect the generator with the recievers. Eg. cable or wire CONTROL ELEMENTS: connect and disconnect different elements of the circuit. Eg. switches & push switches, etc. PROTECTION ELEMENTS: protect and prevent damage to the circuit elements. Eg. fuse, protection switches, etc.

8. ELECTRICAL COMPONENTS COMPONENTS PHOTO SYMBOLFUNCTION GENERATORSGENERATORS PROTECTION ELEMENTS

9. ELECTRICAL COMPONENTS COMPONENTS PHOTO SYMBOL FUNCTION RECEIVERSRECEIVERS Lamp Converts electrical energy into light Buzzer Converts electrical energy into sound Motor Converts electrical energy into rotary motion Resistor It opposes the flow of an electric current Variable Resistors They change the strength of the resistance

10. ELECTRICAL COMPONENTS COMPONENTS PHOTO SYMBOLFUNCTION CONTROL ELEMENTS

11. EFFECTS OF THE ELECTRICITY LIGHT Electricity makes the inside of a bulb shine brightly. Electricity helps people by making heat. Electricity makes movements by making objects vibrate and vice versa. HEAT MOVEMENT

12. TYPES OF CIRCUITS  A series circuit  It is a path which forms one continuous loop; there can be one or more devices in the path.  If a wire breaks, the entire circuit stops working.  A parallel circuit  It is a path that branches; the electricity can follow more than one branch, just like a river that splits into several paths. Each path can have its own switch.  If one of the paths breaks, the others will still work.

13.  Here is a circuit with two bulbs. Notice how the bulbs lie along the path of the electricity. The electric current flows through one light bulb, and then the other. This kind of path is called a series circuit. The bulbs are said to be in a series. When you open the switch, both bulbs turn off. SERIES CIRCUIT

14.  Here is a series circuit with a broken wire. The switch is closed, but neither of the bulbs are lit up. This is because the circuit has been broken. No electricity can flow at all, because there is no complete path from one pole of the battery to the other A series circuit will stop if its broken anywhere. But there is another type of circuit that can allow electricity to flow, even if a wire is broken…

15. PARALLEL CIRCUIT  Here is a parallel circuit. Notice how the path that the electricity can follow branches into three parts. The electricity can choose any of the three paths. It will flow through all three of them, just like a river will branch into three streams. In this example, the switch controls all three lights at once. If you open the switch, all the lights will turn off at once. But what if you wanted to turn off just one light... how would you do it?

16. PARALLEL CIRCUIT  Put switches on each of the branches in the parallel circuit. In our example here, the electricity can flow to both of the light bulbs. But one of the switches has been opened, so that light is off. Even though that path is broken the electricity can still follow the other path, so the other bulb remains lit. This means that a parallel circuit with a break in it could still work…

17. PARALLEL CIRCUIT  Here's a parallel circuit with a break. Notice that one of the paths is broken. But there are still two paths that the electricity can follow, so two of the bulbs remain lit up.

18. Have a nice day !