When cholesterol builds up, the diameter (and therefore the radius) of the arteries decreases. Pressure=force/area. By decreasing the radius of the artery, the area is decreased and Pressure is increased.

The basic fluid dynamics principle is conservation of mass, shown by A1v1=A2v2. Because area is significant, a change in radius, even a small change, can be detrimental because the radius is squared.

Since the build up of cholesterol causes the opening in the ateries to get smaller, the equation A1V1=A2V2 can be applied. As the radius of the artery decreases with cholesterol build up, the pressure increases. This is because the same amount of blood is being forced through a smaller opening. Therefore the heart has to beat more in order to keep up the supply of blood.

When talk about an artery, we think of r^2 meaning that if eventhough r decreses a small percent, it is sqaured making it more significent.

The basic principles is P=pgh. Blood pressure is so sensitive to cholesterol buildup because the surface area decreases when there is a buildup in cholesterol and pressure increases.