A potato helps power a light bulb by acting as both a bridge and a separator for two electrodes made of different metals. The two metals most frequently used are zinc and copper because of their ubiquity and difference in electron affinity. The acid in the potato starts the reaction, and the electrolytes in the potato allow a flow of electrons, an electric current, to flow between the electrodes.Know More
It is important to note that the potato itself is not a source of energy, at least in this case. While it does provide chemicals necessary to get the reaction started, the reaction that produces energy is ultimately between the metals in the two electrodes. However, the metals have a potato between them, and so cannot undergo chemical reactions directly. While metal ions cannot flow through the potato, electrons can. The flow of electrons that results from the chemical reaction is literally an electric current. At least one of the electrodes is gradually worn down by this process, losing mass as solid metal compounds with the potato's chemicals.
The power output of potatoes is very limited, and most light bulbs can be powered only dimly or briefly. With LED lights and a cooked potato, however, scientists have actually achieved impressive results with potato batteries.Learn more about Electricity
Potato batteries use the acids in the potato to start a reaction with two electrodes made of different metals that cause electrons to flow from one to the other through the potato, producing power. The potato acts as a salt bridge, connecting the anode, or negative electrode, to the cathode, or positive electrode. The potato is not a source of electricity by itself.Full Answer >
Connecting a light bulb's electrical contacts to the positive and negative terminals of a battery causes it to turn on and to draw power from the battery. The key to successful connection and operation is matching the bulb's operational range with the battery's voltage.Full Answer >
A light bulb is non-ohmic because it does not obey Ohm’s law. According to Ohm's law, "The ratio of potential difference to the current flowing through a conductor is constant, providing all other influences such as temperature are kept constant."Full Answer >
A PAR light bulb is a light with a parabolic aluminized reflector. The name PAR refers to the shape and design of the light bulb.Full Answer >