Question

why does a fountain pen start leaking at high attitude​

Answer 1

Hey! mate, GOOD EVENING☺

The atmospheric pressure decreases with altitude because gas molecules which make up the air concentrate near lower altitude in response to Earth's gravity. Hence, air pressure islow at higher altitudes. Due to this difference in air pressure, the air inside the pen forces the ink to come out.

Hope it helps you❤❤☺☺

Answer 2

may be it correct or wrong I don't know