Q. Why is it more difficult to breathe on mountains than on plains ?

Q. Why is it more difficult to breathe on mountains than on plains?

A. With higher altitudes, the pressure of air goes on decreasing. The oxygen content in the air is also reduced considerably. We experience difficulty in breathing on mountains because the pressure of air outside is less as compared to the pressure of air inside the lungs.

Q. Why does ink leak out of a partially filled pen when taken to a higher altitude ?

A. The density as well as pressure of air goes on decreasing with altitude. When a partially filled pen is taken to a higher altitude, it leaks, because the pressure of air acting on the ink inside the pen is greater than the pressure of air outside.