Measure content performance. Develop and improve products. List of Partners vendors. Share Flipboard Email. Anne Marie Helmenstine, Ph. Chemistry Expert. Helmenstine holds a Ph. She has taught science courses at the high school, college, and graduate levels. Facebook Facebook Twitter Twitter. Updated February 11, Featured Video. Cite this Article Format. Helmenstine, Anne Marie, Ph.
How Do Pencil Erasers Work? The Science Behind Firecrackers and Sparklers. Today we have erasers of different types, not just shapes. The only problem is as with old erasers that they crumble why doing so and their residue has to be removed.
This is often done with a broad brush. It does not leave behind eraser residue like art gum eraser, and because of the lasts longer, but it loses its efficacy and resilience because particles that it erases stay inside it. Kneaded eraser can be shaped into a fine point to erase small details; it can be shaped into a larger surface and work as a stamp, and it can work as a blotter to lighten a darker area covered with graphite. They cannot erase larger areas because they deform while rubbing.
Because of the way it works it does not smudge or damage work in progress. Before we get to how erasers work, though, let's learn a bit about what exactly is on the paper that you're erasing. It's actually a mineral called " graphite ," which is made up of carbon.
When you write with a pencil, graphite particles from the pencil rub off and stick to the fibers of the paper you're writing on. While pencils are filled with graphite , erasers are made mostly of rubber, although plastic and vinyl are sometimes used. The rubber is usually combined with sulfur to make it last longer. A softener , such as vegetable oil, is also usually added to make the eraser more flexible. Finally, abrasives, like pumice or quartzite, are added, along with dye to give the eraser a particular color.
When you rub an eraser across a pencil mark, the abrasives in the eraser gently scratch the surface fibers of the paper to loosen the graphite particles. The softeners in the eraser help to prevent the paper from tearing. The sticky rubber in the eraser grabs and holds on to the graphite particles. Erasers work because of friction. Try rubbing your hands together right now. Do you feel them getting warmer the longer you rub?
The warmth you feel is the heat generated by the force of friction created by the rough surfaces of your hands rubbing together. As the abrasives in your eraser are rubbed against paper, friction produces heat, which helps the rubber become sticky enough to hold onto the graphite particles. As the rubber grabs the graphite particles, small pieces of combined rubber and graphite get left behind. An English engineer named Edward Naime invented the eraser in Up until that time, people usually used rolled-up pieces of white bread to erase pencil marks.
Erasers help us correct our mistakes, but did you realize they can also be used to make all sorts of interesting crafts? It's true! Take a look at the following art projects, and choose one or more to try:. When you're finished, email or send us a letter with a picture of your eraser art project!
WOW, addison! Thank you for commenting and we hope to hear from you again! We're glad you liked this Wonder of the Day, Wonder Friend!
Thanks so much, Koenig! We think you're on to something cool That's some really creative thinking, Aparajita! We're pretty sure it would just be better for us all to make good decisions about our behavior, though, so we didn't have to worry about needing to erase anything, don't you agree?
We don't think it's weird, Troy, just a little different than what we're used to in modern times! Technology is awesome, isn't it? Who knows what we will be erasing our written mistakes with in the future? There are so many things to learn and explore here! Thank you for leaving us such a nice comment!
Yes, Jacob! It IS made out of rubber! We thought it was interesting to learn that before rubber was used as erasers, people used rolled up pieces of bread! Hi, Mike! Welcome to Wonderopolis! Thank you for leaving a comment and letting us all know there's a real person behind the animation!
Hello, Sister Jane! We are so happy to count you as a new Wonder Friend! Thanks for leaving this great comment today and for sharing Wonderopolis and Thinkfinity with others! Thanks also for sharing Wonderopolis with your colleagues We're liking what we hear, Dee! Thank you for commenting today! Small group discussions can surely lead to bigger discussions and activities when Wonderopolis is part of the day!
Thank you for commenting and sharing this with everyone! What a great idea, Suzanne! Engaging students in research and discovery makes them more equipped to be life-long learners!
Thanks so much for sharing! Hello, Dorene! We really appreciate how you go the extra mile to share Wonderopolis with your fellow educators! Hello, Wendy! Softer rubber erasers require less force and friction, making them less abrasive to paper. White vinyl erasers, for example, erase more cleanly than the common pink eraser because they are made of softer vinyl. Kneaded erasers are moldable and soften when you knead them in your hands.
They're one of the least abrasive erasing tools for removing graphite, charcoal and lead , and because this type of eraser is sticky enough to absorb graphite particles without friction, they leave no smudges, debris or tears. Erasers can do more than erase your unwanted pencil doodles, though. Remember erasable-ink pens? Erasable inks may not be as popular today as they were in the s, but if you're looking for an erasable ink product, they're still out there.
Erasable inks contain liquid rubber cement, which means that unlike traditional inks, these will stick to an eraser if you erase them within 10 hours of writing otherwise the rubber hardens and can no longer be lifted from the paper. Products like magic erasers can take marks off of a number of surfaces, but give your standard pink pencil eraser a try on some of those scuffs. You might be surprised at how effective it can be at erasing more than just pencil marks. About 75 percent of the pencils sold in America are painted yellow [source: Ritter ].
I learned something new about pencils while researching this article.
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