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“Lightning never strikes the same place twice” is a common phrase you’ve probably heard before, often used to reassure someone that whatever bad thing has happened, it won’t happen again. It can even be used when something good happens, such as winning the lottery, but the underlying truth remains. What are the odds that something extremely unlikely, such as a lightning strike, will happen more than once? After all, a thunderstorm travels across an area. So after lightning strikes one place, it’s probably safe from another strike. In reality, lightning can and will strike the same place twice, whether it be during the same storm or even centuries later.

When we see a lightning strike, we’re witnessing the discharge of electricity that has built up in a cloud, which is so strong that it breaks through the ionized air. This creates a stepped leader, or the lightning bolt, that travels downward until it reaches the ground. It is an incredibly quick process that takes only about 30 milliseconds. And right after lightning strikes, it reverberates in quick succession. So, essentially, multiple strikes can happen at the same place in this short period of time. Technically, the lightning is already striking more than once. Even during the same thunderstorm, there is nothing stopping a lightning bolt from striking the same place it had struck previously, even if it was as little as a few seconds earlier or as much as centuries later.

In the U.S. alone there is an average of 20 million cloud to ground lightning strikes per year. This makes the likelihood of a place being struck by lightning multiple times incredibly high over a long period of time. If anything, if there is a significant attraction between the bolt and the place it previously hit, it’s more likely that the same place would be struck again. Skyscrapers are more susceptible to strikes since they significantly reduce the distance the stepped leader needs to travel. For instance, famous skyscrapers like the Empire State Building in New York City and the Willis Tower in Chicago are nearly guaranteed to be struck by lightning each time a thunderstorm passes overhead—but don’t worry, they have built-in lightning rods to make sure no damage is done to the building!

Nora Gonzalez

static electricity, form of electricity resulting from the imbalance between positive and negative charges within a material that occurs when electrons (the negatively charged particles in an atom) move from one material to another. If the electron-receiving material is either isolated or not an electrical conductor, it tends to hold on to the electrons, resulting in a buildup of electric charge. Since this charge is not moving, it is referred to as static electricity. When conditions allow the built-up charge to flow, the surplus of static electricity is discharged, and it becomes current electricity.

How static electricity forms

When different atoms make contact with one another, electrons can transfer between them. The material shedding electrons also loses negative charge, and it becomes positively charged when there are more protons (positively charged particles) than electrons. Conversely, a material that gains electrons becomes negatively charged. As more electrons move from one material to the other—due to repeated contact between them—additional negative charge will build up in a process that is referred to as the triboelectric effect.

Examples of static electricity

If two objects are rubbed together—especially if the objects are insulators and the surrounding air is dry, such as when a person’s feet move across a carpet—they acquire equal and opposite charges, and an attractive force develops between them. In this example, the atoms in the person’s body strip away electrons from the carpet and leave behind a positive charge on the carpet’s fibres. The electrons become isolated in the atoms of the person’s body. However, when the person gets close to a conducting material, such as when reaching out a hand to touch a doorknob, a path to ground the built-up charge emerges, and electrons jump suddenly to the conducting material. In addition, as the person reaches for the doorknob, some strands of hair may stand on end. Because like charges repel each other, the transferred electrons that build up in the body travel to the extremities—such as individual strands of hair. (This phenomenon can be demonstrated by using a Van de Graaff generator, which uses a moving belt to gather electric charge on a metallic sphere.)

battery. Illustration of battery connected to lightbulb. Power a light bulb with a battery. Battery, Power Supply, Science, Circuit, Currents
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Electricity: Short Circuits & Direct Currents

Another example of the effects of static electricity can be observed in a lightning strike, which occurs when a region of a cloud accumulates a surplus of electrical charge. Small hail particles form in a cloud when moisture in the air freezes, and these particles transfer charge as they grow, move within the cloud, and collide with one another. As additional charged hail particles form, a charge separation occurs, with air acting as an insulator between the charged particles in the cloud as well as between the cloud and the ground. When the surplus of charge is great enough, it overcomes the insulating ability of the air, and electricity is discharged between clouds or between the ground and the cloud itself.

Uses of static electricity

Some of the best-known uses of static electricity occur in air filters and dust-removal devices, which take advantage of the charge differences between materials to remove airborne particles. As electrostatically charged air particles pass through the filter system, the layers of the filter, which have an opposite charge, pick them up and trap them. The buildup of static charge is not always beneficial, however. It can cause damage to important electrical components in computer chips and other components in circuits. Additionally, the friction that occurs while pumping liquids through hoses or pipelines can cause a static charge to accumulate, which can be hazardous if these liquids or the gases they produce are flammable. When this static charge comes into contact with a grounded object, it can create a spark that could ignite these materials.

Ken Stewart