Electricity (Year 3)

Electricity (Year 3)

What is the definition of “electricity”?

Electricity is a form of energy usually carried by wires or produced by batteries used to power machines and computing, communications, lighting, and heating devices.

We use electricity every day. Appliances at home such as television, fan, water heater and refrigerator work when electricity flows through them in a complete circuit. An electric current does not flow through an incomplete circuit.

 

Diagram 1: A Complete Circuit

How Does a Bulb Lights Up Brighter or Dimmer?
A bulb lights up when electricity flows through a complete circuit which consists of a bulb, wires and a battery ( Diagram 1 ). Electricity flows from the positive battery terminal across a complete path toward the negative terminal. 

Diagram 2: Bulb Lights Up Brighter

A bulb is brighter when more electricity flows through it. How? By adding one more battery to the circuit ( Diagram 2 ). The number of batteries used affects the brightness of a bulb in a circuit. But another battery further added to the circuit, the bulb will blow because there would be too much energy passing through the circuit.

Diagram 3: Bulb Lights Up Dimmer

A bulb is dimmer when less electricity flows through it. How? By adding another bulb to the original circuit ( Diagram 3 ). This is so because two bulbs sharing the power of one battery.