Energy transformation

Voltage, also known as "potential difference" can be measured by a device called a voltmeter. 

 Similarly, current can be measured with an ammeter. ( coloumbs charge / second)

We also watched a small video explaining energy transformation from a battery to the circuit. The battery charges electrons and sends them to the load. There, the electrons let off energy which transforms into heat. The electrons then travel back to the battery to become charged again.