1. IP2.24.3 d.c. devices © Oxford University Press 2011 d.c. devices

2. IP2.24.3 d.c. devices © Oxford University Press 2011 All electrical devices use either alternating current (a.c.) or direct current (d.c.). Here are some devices that work with d.c. current.

3. IP2.24.3 d.c. devices © Oxford University Press 2011  Direct current has a constant potential difference and is normally produced by cells and batteries.  This means that the current is always in the same direction.  The electrons always flow round the circuit in the same direction.

4. IP2.24.3 d.c. devices © Oxford University Press 2011  The mains supply in the UK is an a.c. supply.  In order to charge the batteries of devices that use d.c. currents from the mains an a.c. adapter is required.  This adapter changes the a.c. supply current into a d.c. current suitable for the device.  In order to save energy there are now solar chargers available to charge devices like phones and mp3 players. These chargers harness the Sun’s energy and produce a d.c. current without using energy from the mains or a.c. adapters.