Why do plastic bottles “suck” themselves in when the plane is descending?

Question

Why do plastic bottles “suck” themselves in when the plane is descending?

In: 3

Answer 1

Think of putting a balloon in the vacuum hose. When the vacuum is off the pressure around the balloon reduces, so the balloon is round.

When you turn the vacuum on the balloon changes shape, like a water bottle on an airplane, because the air pressure around the balloon has increased.