What pressure change occurs in the bell jar when the diaphragm is pulled down?
Regarding this, what happens to the pressure of the air inside the bell jar when the stretchy rubber is pulled downwards?
The cavity inside the bell jar is airtight. As the diaphragm is pulled down, the volume of the cavity increases. This causes the pressure to decrease. This causes an increase in pressure within the bell jar, the air rushes out of the balloons causing them to deflate.
Herein, what happens when the diaphragm is pulled down?
When you breathe in, or inhale, your diaphragm contracts and moves downward. This increases the space in your chest cavity, and your lungs expand into it. The muscles between your ribs also help enlarge the chest cavity. They contract to pull your rib cage both upward and outward when you inhale.
This increases the size of the thoracic cavity and decreases the pressure inside. As a result, air rushes in and fills the lungs. During expiration, the diaphragm relaxes, and the volume of the thoracic cavity decreases, while the pressure within it increases. As a result, the lungs contract and air is forced out.