Activity 1.1 - Electric current, battery and bulb

• To understand how a potential difference can cause an electric current through a conductor
• To learn to design and construct simple electric circuits using batteries, bulbs, wires and switches
• To learn to draw circuit diagrams using symbols

• A few cheap torches that can be taken apart,
• Three bulbs (e.g. 4,5V/0,3A), Zinc-carbon battery (4,5V), leads, one-way switch, two-way switch

Divide the class into small groups of 2-4 students and hand out the worksheet: Electric current, battery and bulb. The students working in groups go step by step from simple observation to guided discovery up to bounded inquiry.

Let students play in groups with a torch and dismantle and examine its components. Students should identify three basic components: a switch, a bulb and a battery that are connected in series. They learn that for current to flow the closed circuit is needed. The torch case can be a part of the circuit.

After this first simple investigation they learn to build their own simple electric circuit from a battery, a bulb, leads and a switch.
Once the students know to light up a single bulb, they can design and build some simple electric devices using extra switches, wires and bulbs. They are asked to invent and construct more complicated circuits with series or parallel connection of bulbs using switches. Even if the students do not know what goes on in electric circuit in details, this task can motivate them to think and investigate in order to find out the appropriate solution. Students are engaged in design of a model of electric devices that are commonly used in real life.

Students should work on their own realizing bounded inquiry. Once they have completed the investigation they summarize the results and present them to the other groups. In case we do not have all materials for each group or we are lack of time, each group can construct one of the suggested electric circuits.

• What are the torch basic components?
• What makes the bulb light up?
• What components can a simple electric circuit be made of?
• What influences the bulb brightness?
• How is the current direction set?
• How do different switches work?