Uncovering the Origin of Static Electricity: Potential Discovery by Scientists
Out and about, scientists at Northwestern University have potentially cracked the code on why certain actions, such as walking in socks on carpet or rubbing a balloon on your head, generate static electricity. In a new investigation, they disclosed that rubbing can bring about microscopic deformations on an object's surface, which enables the occurrence of this peculiar electricity phenomenon.
Since ancient times, the existence of static electricity has intrigued individuals - the Greek philosopher Thales of Mileus reportedly noticed the fascination between fur and dust following friction with amber in 600 B.C. Over time, scientists discovered that diverse substances could generate static electricity, and ticks are known to use this power to boost their host-grappling range. However, the basics behind static electricity remained cloaked in mystery, primarily the role of rubbing in its creation.
Thales of Mileus in 600 B.C. (Thales noticed that fur would attract dust right after it was rubbed with amber). Since then, we’ve learned that lots of things can cause static electricity and that it can be advantageous to animals, such as ticks that use static electricity to
Launching into excitement, lead researcher Laurence Marks, an Emeritus Professor of Materials Science and Engineering at Northwestern, shared, "For the first time, we can clarify a mystery that nobody could before: why rubbing matters." He asserted that this occurred due to microscopic surface deformations prompted by the process of rubbing, which ultimately leads to the creation of voltage.
extend their host-grappling range. But scientists have remained in the dark about many of the basics behind static electricity, particularly why rubbing often induces it—at least, perhaps, until now.
Generally, rubbing two distinct materials results in separation of electrons, rendering one material positively charged alongside the other negatively charged or vice versa. When these materials finally come in contact again, they attract each other since their charges differ, leading to rapid electron movement between them. This rapid transfer of electrons also explains why static charge arises when rubbing your feet against a carpet and touching a metal doorknob.
statement from the university. “People have tried, but they could not explain experimental results without making assumptions that were not justified or justifiable. We now can, and the answer is surprisingly simple.”
Moreover, rubbing identical materials can also initiate static charge, contradicting the common perception that this could only transpire through rubbing materials of differing sizes. In this study, Marks and his team have proposed another significant mechanism to explain how rubbing causes static electricity, focusing on the component of elastic shear, referring to a material's ability to endure sliding on a surface. They argue that by increasing friction due to elastic shear, the front and back of an object can display contrasting deformations that carry opposing charges, consequently leading to static electricity manifestation.
basic principle of the trick is that rubbing two objects with very different physical properties causes one object (our hair, in this example) to lose electrons and become positively charged and the other object to become negatively charged (gaining electrons). When the objects then meet again, the difference in charge causes them to be attracted to each other and for electrons to rapidly move from one to the other. This rapid movement of electrons also explains why rubbing our feet along our carpet and then touching a metal doorknob can cause a small shock. But rubbing pieces of the same material can also generate static charge, and
Marks mentioned, "In 2019, we had a hint of what was occurring. However, like a seed, it required time to grow. Now, it has bloomed. We developed a new mathematical model that calculates electrical current, and the data obtained was aligned with the experimental results."
previous research seems to have debunked a common explanation for why this can happen (the argument was that this charge could be created by rubbing pieces of the same materials with two different sizes).
Though scientists require further research to verify the discoveries, this hypothesis may potentially shed light on numerous instances of static electricity, including same-material rubbing. As explained, it doesn't clarify every case, but the fact that the field of science continues to unfurl mundane mysteries is comforting, as it implies that there's always more to learn and understand about our world.
published last month in the journal
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published a study finding that the mere act of rubbing two materials together can cause small deformations on the surfaces of the objects, which create voltage. But they’ve now worked out exactly how rubbing can lead to static charging, which is influenced by the existence of elastic shear, or a material’s ability to resist sliding when moving along a surface (this is why we eventually stop sliding on a floor even when wearing socks). They argue that the increasing friction caused by elastic shear means that the front and back of an object can have different deformation that carry opposing charges, which then allows static electricity to happen, akin to how the difference in air pressure above and below a plane’s wing causes lift.
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In light of the new study, scientists can now explain why rubbing causes static electricity, challenging previous beliefs that it only happens with materials of different sizes. They attribute this phenomenon to the existence of elastic shear, a material's ability to resist sliding, which increases friction and results in contrasting deformations carrying opposing charges, thereby causing static electricity.
This research could potentially shed light on various instances of static electricity, including the same-material rubbing situation. The researchers published their findings in the journal of Physics Letters, highlighting that the rubbing process leads to small surface deformations, creating voltage.
The study's implications extend beyond our understanding of static electricity. As Marks, the lead researcher, explained, their new mathematical model calibrates electrical current and aligns with experimental results, potentially opening new avenues in physics and technology.
In the future, this discovery could lead to advancements in areas such as technology and electricity generation, providing scientists with a deeper understanding of the fundamental principles behind these phenomena.
