LEARNATHON
III

Competition for grade 6 to 10 students! Learn, solve tests and earn prizes!

### Theory:

In order to use the electrical energy, the current has to be passed through various electrical components arranged systematically.
An electric circuit is a continuous closed path or loop along which current flows from the positive terminal to the negative terminal of the battery. It has a network of electrical components through which electrons flow.
An electric circuit
Components of the circuit:
An electric circuit consists of four main components. They are
1. A cell or a battery
2. Connecting wires
3. A switch
1. A cell or a battery:
A cell or a battery is a device that converts chemical energy into electrical energy, thus producing a small amount of electricity.
A cell is a single unit, whereas a battery is a collection of two or more cells.

Cell

2. Connecting wires:
The conducting wires connect the electrical components and act as a path for the current to flow. The wires can be seen when an electrical appliance is connected to a battery or a source of electric charge. The symbol for the wire is a single straight line.

Conducting wires

Switch:
An electric switch or a key is connected to the circuit to stop or allow the current flow.
If a key is switched off, the current will not flow across the circuit; thus, it is an open circuit. A lamp does not glow in this type.
If the key is switched on, the current will flow, making it a closed circuit. A lamp glows in this type.

A switch

Resistor:
The resistor is used to control the amount of current flowing through the circuit. The resistor can be fixed or variable.
Fixed resistor:
A fixed resistor has a definite or a fixed value that cannot be changed.

Fixed resistors

Variable resistor:
A variable resistor or a rheostat controls and selects the amount of current flowing through a circuit.

Rheostat

In an actual circuit, many other electrical components are also used. Some standardised and uniform set of symbols has been developed to describe the electrical components in circuits.

Electric circuit diagram:
A circuit diagram helps to represent electrical wiring or to solve problems involving electric circuits.

A circuit diagram
Reference:
https://live.staticflickr.com/156/437342078_b0d773a9a3_b.jpg