1. Switches in Series A heating system is a practical circuit used in homes which has two switches in series. The thermostat switch opens (OFF) when the temperature rises above 20˚C. The heater could also be switched off by either switch though as both are in series. +- On / Off Switch for Heating Automatic Temperature Control Switch (Thermostat) Heater

2. Car Wiring A car battery is 12 V d.c. All electrical components in a car are wired in parallel. Since the voltage across all components wired in parallel is equal to the supply voltage, all components wired in a car operate at 12 V.

3. side lights head lights brake lights ignition switch 12 V battery The four side lights of a car are controlled by one switch. If one goes out, the rest stay on. The two headlights are controlled by one switch and work in the same way. horn M motor for window wipers