High School Physics

# Static Discharge and Lightning

Last updated on May 14th, 2022 at 02:24 pm

In this post we will find what static discharge is and how lightning occurs. Also we will answer a few FAQs on static electricity.

## What is static discharge – can you explain with an example?

The sudden flow of electrons is static discharge. This can be explained with the incident that happens when you have become negatively charged and your hand approaches the metal doorknocker.

Your negatively charged hand repels electrons in the metal, so the electrons move to the other side of the knocker. This makes the side of the knocker closest to your hand positively charged.

As your negatively charged hand gets very close to the positively charged side of the metal, the air between your hand and the knocker also becomes electrically charged. This allows electrons to suddenly flow from your hand to the knocker.

The sudden flow of electrons is static discharge. The discharge of electrons is the spark you see and the shock you feel.

## How Lightning Occurs?

An example of static discharge, on a much larger scale, is lightning. You can see how it occurs in the following diagram as you read about it below.

During a rainstorm, clouds develop regions of positive and negative charge due to the movement of air molecules, water drops, and ice particles. The negative charges are concentrated at the base of the clouds, and the positive charges are concentrated at the
top.

The negative charges repel electrons on the ground beneath them, so the ground below the clouds becomes positively charged. At first, the atmosphere prevents electrons from flowing away from areas of negative charge and toward areas of positive charge.

As more charges build up, however, the air between the oppositely charged areas also becomes charged. When this happens, static electricity is discharged as bolts of lightning.

## What Is Static Electricity?

Static electricity is a buildup of electric charges on objects. Charges build up when negative electrons are transferred from one object to another. The object that gives up electrons becomes positively charged, and the object that accepts the electrons becomes negatively charged. This can happen in several ways.

One way electric charges can build up is through friction between materials that differ in their ability to give up or accept electrons. When you wipe your rubber-soled shoes on the wool mat, for example, electrons rub off the mat onto your shoes. As a result of this transfer of electrons, positive charges build up on the mat and negative charges build up on you.

Once an object becomes electrically charged, it is likely to remain charged until it touches another object or at least comes very close to another object. That’s because electric charges cannot travel easily through air, especially if the air is dry.

## You’re more likely to get a shock in the winter when the air is very dry. Can you explain why?

When the air is very dry, electric charges are more likely to build up objects because they cannot travel easily through the dry air. This makes a shock more likely when you touch another object.