Soap Dispenser

Aim: This activity is used as an analogy for how electric circuits work. 

Equipment: The equipment includes... 

• Empty hand soap dispenser with a hole in the bottom;
• Bowl of water;
• clear plastic hose;

Method: Get an ordinary hand soap dispenser and drill a hole in the bottom. Place water in a bowl and attach a clear plastic hose to the nossle of the hand pump. Sit the dispenser in the bowl of water. Pump the hand pump to demonstrate the movement of liquid from the bowl through the dispenser and nossle and back into the bowl. 

Background knowledge: The water in the bowl is the electric current (or electrons - tiny negatively charged particles that flow through the wires). Electric current acts similarly to this. The pump is the typical battery that provides electric energy to force the current to flow through the rest of the circuit. If the circuit is cut (ie. the hose is removed from the water in the bowl), the circuit does not work properly. Electrons and electricity require a complete pathway for electricity to flow: from one end of the battery to the other.