Researchers at Northwestern University’s McCormick School of Engineering think they may have cracked the code on how static electricity occurs.

The scientists found that when two objects are rubbed together, the bending of tiny protrusions on their surfaces creates voltage – something called triboelectricity, or static electricity.

Professor Laurence Marks, who teaches material science and engineering, and two doctoral students, Christopher Mizzi and Alex Lin, published their findings in September in the journalPhysical Review Letters.

“What we found is that the way that friction or sliding leads tostaticelectricity is because you bend very small protuberances on materials,” Marks said. “And when they bend, that gives you a voltage and that voltage is what forces electrons to go from one material to another.”

That imbalance of negatively charged electrons hopping from one object to another causes a shock someone might feel after, say, dragging their feet along a carpet and then touching a metal doorknob.

Marks said a buildup and discharge of static electricity can be deadly in chemical plants or when refueling aircrafts. He saidtheir researchcould help control for dangerous situations.

“One of the things in the paper is we have a little formula that you can use to estimate how muchstaticelectricity you will produce for a particular type of material,” Marks said. “So if you want to make morestaticelectricity, then you change certain properties of the material; if you want to make less, then you do the opposite.”

Marks joins us Thursday on “Chicago Tonight” to further discuss his team’s research.