Question

Imagine that you are going on an airplane trip in an unpressurized plane. You are bringing aboard an air-filled pillow that you have inflated fully. Predict what will happen when you try to use the pillow while the plane is at cruising altitude.

Answer 1

On the ground, the air pressure inside and outside the pillow balance one another. Atmospheric pressure decreases with altitude, so in an unpressurized plane, the air-filled pillow may explode because the air pressure inside it outweighs the external pressure.

Answer 2

nothing good I can guess

Answer 3

may or may not explode, but it's volume will definitely increase.