A rainbow of mucus and phlegm. As far as color goes, mucus is typically clear. But when the immune system sends white blood cells into the nose to fight off infection, they contain a greenish enzyme that shades the substance yellow or green.These are the same tones mucus takes on when it dries and clumps into boogers.s far as color goes, mucus is typically clear. But when the immune system sends white blood cells into the nose to fight off infection, they contain a greenish enzyme that shades the substance yellow or green. These are the same tones mucus takes on when it dries and clumps into boogers.
#3. Sandy_221. I think if the object that is acted upon is on the the X-Y plane, for example, then an applied force can't be considered a normal force if the former is in the same plane as the latter. In order for an applied force to be a normal force it has to be on the Z plane. Is this right? What do you think, guys?
Force is a quantitative description of an interaction that causes a change in an object's motion. An object may speed up, slow down, or change direction in response to a force. Objects are pushed or pulled by forces acting on them. Contact force is defined as the force exerted when two physical objects come in direct contact with each other. Other forces, such as gravitation and electromagnetic forces, can exert themselves even across the empty vacuum of space.