Question

An electric field of $5,000,000\frac{V}{m}$ is applied across a region filled with air at atmospheric pressure. What will happen? (Dielectric strength of air is $3,000,000\frac{V}{m}$

• A. Nothing happens
• B. Fusion reaction takes place between air molecules
• C. Air begins to conduct and we get sparks
• D. The zombie apocalypse starts

Answer 1

The correct option is C Air begins to conduct and we get sparks

So whenever air or any other dielectric material is subjected to an electric field higher than the material’s dielectric strength, some of the molecules ionize and the ions produced conduct charges which move along the field. This usually produces sparks in air.
In fact, lightning is an example of this phenomenon.