How Does a Pencil Eraser Work?

Have you ever stopped to think about how an eraser (or rubber) works? Is it entirely down to friction, or is it stickiness? About.com Guide to Chemistry, Anne Marie Helmenstine, explains in her article How Do Pencil Erasers Work?

See Also:
• What's a Putty Eraser?
• Erasers Aren't Just for Removing Mistakes
• May I use an Eraser? (From About.com Guide to Drawing / Sketching)

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