Electricity

3E: Tuesday 16th November

Unit 2: Using Electricity

Using Electricity

From the wall socket

• Household appliances• Safety

A.C. and D.C.• Circuit diagrams• Current and Voltage• Battery and Transformer

Resistance

• Variable resistors and their uses• Electrical Power• Lamps and heaters

Useful circuits• Series and Parallel• Fault finding

Behind the wall • The mains supply• Domestic electricity meter

Movement from Electricity

• Electric motor

Using Electricity

• What is electricity?

• Why do we use it?

• What is a circuit?

Model of current flowBakery

Supermarket

1. Bakery Manager loads bread onto the vans and sends them off

2. As soon as the vans start to move, bread is delivered to the supermarket.

3. All the vans move at the same speed.

4. If the manager speeds the vans up, more bread is delivered to the supermarket in a certain time.5. If the manager loads more bread on each van, more bread is delivered to the supermarket in a certain time.

The vans deliver the bread to the supermarket where the shoppers take it away.

The empty vans go back to the bakery to get more bread.

Each van takes bread to the supermarket.

Empty vans collect bread at the bakery.

Model of current flow1. The battery provides energy and makes the charges move.

2. As soon as the charges start to move, energy is delivered to the bulb

3. All the charges move at the same speed

4. If the charges speed up, more energy is delivered to the bulb in a certain time.5. If more energy is carried by each charge, more energy is delivered to the bulb in a certain time.

Charges deliver energy to the bulb where it is transferred to heat and light.

Charges return to the battery to collect more energy.

Charges are atom sized particles already in the wire. The charges carry energy.

Charges collect energy at the battery.

The electric current (Amperes) is the number of charges passing a point each second