We use electricity to make all sorts of things work, without really knowing what's going on. One important hint about the nature of the electrical connection comes when we notice that an electrical plug has at least two prongs. Just as a road has two lanes so that cars can come and go, the wire has two strands so that electrical current can come to the device and then return to the power source. It suggests that something is flowing in the wire.

Various electrical devices. a buzzer, holder, a battery, a light bulb, a motor, wires with clip ends

Materials needed for this section

• Batteries *
• motor *
• light bulb *
• wires with clip ends *
• buzzer *
• materials to use to make switches: aluminum foil, tape, cardboard or cardstock, paper clips, rubber bands, plastic straws, ... (you provide)
• scissors
• aluminum foil *
• Thermal sensing sheet (it changes color when you touch it)*

Another page you might find interesting:
Why study electrical current?

Next section:Direction of current