A Wonderleaf question
How does a ballpoint pen draw ink?
a real page from the book
A ballpoint pen writes because a tiny metal ball turns at the tip. As you move the pen, the back of the ball gathers a thin film of ink from inside, while the front rolls that ink onto the paper in a steady line.
The ink is thick on purpose, so it does not gush out when the pen is resting. The ball works as a small valve, opening only as it rolls. That is why a pocket pen can wait quietly, then write the moment paper grabs the tip.
Wonder words
- socket
- ink
- friction
- valve
Try it out
Use a clear-tipped pen or an old ballpoint, make slow dots and lines, and watch how pressure changes the mark.
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