Question

Why don't trachea or windpipe doesn't collapse when there is no air inside?

Answer 1

The trachea is a tube which is narrower and this helps in connecting the pharynx to the bronchi of the respiratory system.

The trachea is supported by the series of the cartilaginous rings which are c-shaped, this prevents it from collapsing, these rings can be felt in front of the neck.

If you place the fingers in front of the neck and slip them against the neck these rings can be observed.