Work Step by Step
Of the circuits, only #5 is a complete loop. Circuits 1 and 2 connect the positive terminal to the negative terminal with a wire. This is known as a short circuit and will result in a large current that will drain the battery. Circuit 3 has each end of the lightbulb filament connected to one battery terminal, which places both ends of the filament at the same potential. No current will be driven. Circuit 4 has only one end of the lightbulb filament connected. The glass bulb will not conduct.