Dismantling 10 frequent myths about electricity

Myth no. 1: batteries store electricity inside

Many people believe it, and they say that batteries store an electric charge or electrons inside.

Reality.If we opened a battery, we’d find a chemical liquid, something similar to soup. It’s called electrolyte and is conserved between two electrodes: the positive and the negative. By inserting the batteries into an apparatus, the electrolyte transforms into ions and the electrons are discharged from the positive electrode.

Conclusion: inside a battery, there is no electricity; rather, there is everything necessary so that, when the time comes, the electricity flows.

Myth no. 2: the electrical current depends on how thin the cable is

Some think that the thinner a cable is, the more electrical current passes through it, given that it faces less resistance. Or the opposite: some think that a very thick cable transports more current because by being bigger, it “fits” more inside.

Reality. Cables simply don’t work that way. In order to be able to understand it, let’s take a river as an example. In the widest areas, the water is calmer. In the narrow stretches, the water flows quickly. However, the quantity of litres that go to the sea is always the same.

Myth no. 3: electricity has zero mass and zero weight

Though the terms “intuitive” and “common sense” are trendy now, we can’t always let ourselves be guided by our first impression. If you ask someone how much electricity weighs, they’ll probably tell you nothing.

Reality. The fact that we can't see it does not mean that electricity does not have mass or weight. The movement of electrons has mass and weight, though they're almost invisible.

Myth no. 4: the low-voltage discharges are not dangerous

Everyone is clear that high voltages pose a fatal danger, as we sometimes see in films. To compensate, many believe that low voltage means little more than a shock.

Reality. Like a high-voltage shock, low-voltage ones can be dangerous and even cause death in some cases.

Myth no. 5: rubber and wood objects are the best insulators

Reality. It’s true that both materials are good insulators, but they're not sufficient to prevent an accident. Objects are rarely pure rubber. For example, when we wear some shoes or gloves, in addition to rubber, they include other additives that provide resistance and durability.

“The thickness and size of a cable have nothing to do with the quantity of electricity that circulates inside it.”

Myth no. 6: an electric generator creates electricity

It seems like a pure result of the wording: if it’s called a generator, it’s because it generates electricity, right?

Reality. As incredible as it may seem, generators do not create electricity by themselves. They merely transform it: mechanical energy transforms into electrical energy, causing the electrons of the cables and circuits to flow.

Myth no. 7: electricity travels at the speed of light

This is another apparent truism that turns out not to be true. If it is light, it must travel at the speed of light, right?

Reality. The speed of electricity depends on the means on which it travels. Inside a cable, there are many resistances. Though when electromagnetic waves travel on a suitable conductor, they travel at speeds close to the speed of light (between 50% and 99%), electrons are much slower.

Myth no. 8: an apparatus that is turned off does not consume electricity

Luckily, fewer and fewer people believe this myth, given that the stand-by or ghost consumption has started to be recognised in all homes.

Reality. Even if it's turned off, it can remain plugged in (or worse: with a red pilot light turned on). This is called stand-by or ghost consumption. In some cases, there are apparatuses that consume practically the same when they are turned on and on stand-by. For example: cell phone charges, televisions, microwaves, coffee makers, satellite TV decoders...

“The cell phone charger and television consume practically the same when they are turned on and when they are on stand-by.”