An electric current can flow in the wire from one end ... The bigger the difference in energy, the bigger the potential difference. For example, 230 V is a bigger potential difference than 12 ...

To measure the current flowing through a component in a circuit, you must connect the ammeter in series with it. Remember, electric current is measured in amperes, or amps for short.

Scientists worked with electricity long before they understood that current was made of electrons. The cathode tube was a prime example. By switching on some voltage, scientists could make ...