Question

In a fountain pen ink does not run out by its own.why​

Answer 1

Answer:

due to high atmospheric pressure.

In aeroplane atmospheric pressure gets ready reduced so ink can come out of the pen. that is why it is advised to take out ink before flying✈

Answer 2

Answer:

vacuum , the same way water wont run out of a straw when you hold your thumb at the top and pull water out of a cup