Why Does Ink Not Spill Out Of A Ballpoint Pen?
| Updated: 19 Dec 2017
Mystery Hour Question
When you’re writing using a ballpoint pen, why doesn’t the ink leak onto the paper?
Angela, Epping
Answer ** Definitive **
Name: Dean, Wigan
Qualification: A-level physics
Answer: It’s to do with atmospheric pressure. There is pressure pushing into the pen which keeps the ink in place. Because it is completely airtight at the top, there’s no pressure form the other side to push it out.