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.
It is the force that allows satellites, including natural ones like the moon, to stay in orbit around the Earth, and the Earth to stay in orbit around the sun. The most basic equation for force is: force equals the mass of an object multiplied by its acceleration. To calculate the force of Earth's gravitational field, acceleration is substituted with the measured acceleration of gravity, which is 9.81 meters per second squared.