Green or Dark Yellow Phlegm. A thick and dark yellow phlegm may be a sign of a viral or bacterial infection, sinus infection, or lower respiratory tract infection. Typically, this occurs when the immune system sends white blood cells, known as neutrophils, to the area of infection.ink Phlegm. Pink-colored phlegm is anything but pretty. Coughing up pink phlegm is an indicator of pulmonary edema, also known as fluid in the lungs. It can also be a sign of bleeding when seen in small amounts, which show up as a stain or streak.
The normal force, which is the force that supports the weight of an object on a surface, acts in the opposite direction of gravity. Most often, we see this with objects at rest on a horizontal surface, like a book on a table or someone standing on a floor.
Buoyant force refers to the amount of pressure exerted on a particular object when placed on some kind of fluid.In scientific terms, fluids may either be liquid or gas. This concept is based on the Archimedes principle that the force acting on an object in a liquid is equal to the weight of the displaced fluid.his explains why the buoyant force or pressure at the bottom of a particular object is greater than the force on top. And regardless of the objectâs weight or density, whether it floats or sinks, some buoyant force is still present.